AGTP Standard Extended Method Vocabulary

Introduction

Motivation The AGTP core specification deliberately limits its Tier 1 method set to twelve methods that represent the universal operations of AI agent systems: data retrieval, content synthesis, resource booking, scheduling, context management, delegation, collaboration, confirmation, escalation, notification, capability discovery, and session suspension. This minimalist core enables broad baseline compliance without requiring implementations to support methods they do not need. Real-world agent deployments require a richer vocabulary. An agent performing data analysis needs ANALYZE, CLASSIFY, and EVALUATE. An agent connecting enterprise systems needs SYNC, MERGE, and CONNECT. An agent managing complex workflows needs CHAIN, BATCH, and RUN. An agent executing commercial operations needs AUTHORIZE, CANCEL, and PURCHASE. These operations are well-defined, widely needed, and deserve standardized method names, but they are not universal enough to belong in the Tier 1 core. This document defines the Tier 2 Standard Extended Method Vocabulary: a registered set of methods available to any AGTP implementation. Tier 2 methods are not required for AGTP compliance but SHOULD be implemented where their semantics apply.

Empirical Justification Agent Transfer Protocol is motivated by measured agent performance gains. Independent benchmarking (4,800 trials across Claude, Grok, and OpenAI-family models) compared pure CRUD endpoints against a mixed catalog containing both CRUD and the semantic verbs defined in this vocabulary. In mixed-paradigm conditions (Tier 1 CRUD + optional Tier 2 semantic methods), agentic verbs improved exact-match accuracy by 10–29 percentage points depending on model family (Claude +29 pp, Grok +18 pp, OpenAI +10 pp; all p<0.001). Parameter fidelity and clarification rate also improved. A description-swap ablation (J1/J2) isolated the mechanism: when CRUD paths received agentic-style descriptions, performance collapsed dramatically on weaker models (Grok -39 pp, OpenAI -43 pp). When agentic paths received CRUD-style descriptions, performance held nearly flat on Claude and degraded far less on other models. This demonstrates that semantic method names encode intent more resiliently than REST-style generics, even when documentation quality varies — precisely the scenario Tier 2 methods are designed to address. Two-stage discovery (as required by AGTP session establishment) incurs a modest cost (12–17 pp) but does not erase the net gain. The QUOTE method and Supported-Methods header further reduce unnecessary invocations. These results validate the tiered design: Tier 1 provides the operational simplicity developers require, while the registered Tier 2 vocabulary delivers measurable agent performance and resilience. Implementations are encouraged to adopt Tier 2 methods where their domain semantics align.

Taxonomy Methods are organized into six categories. Each category has a distinct operational character:

ACQUIRE:: Retrieve data, resources, or state without modifying it. Agents observe, locate, and extract information.
COMPUTE:: Process or transform information to produce a derived result. Agents analyze, classify, summarize, and generate outputs.
TRANSACT:: Execute operations that alter system state or complete an external commitment. Agents book, purchase, authorize, and register.
INTEGRATE:: Connect, synchronize, or unify data and services across system boundaries. Agents merge, link, sync, and map across silos.
COMMUNICATE:: Deliver signals, messages, or structured outputs to recipients. Agents notify, alert, broadcast, and reply.
ORCHESTRATE:: Coordinate, sequence, and manage workflows across tasks, agents, and time. Agents chain, batch, route, and schedule.

The category taxonomy aligns with the ACTION framework defined in . The INTEGRATE category is the key distinction from simpler models: cross-system unification operations are neither transactions (no external commitment) nor computations (no transformation of content into a new analytical form). They are connective operations with distinct failure modes, conflict policies, and reversibility characteristics.

Method Registration All methods in this document are registered in the IANA AGTP Method Registry per the registration procedure defined in Section 9.2. Implementations MUST list supported Tier 2 methods in the Supported-Methods response header at session establishment. Clients SHOULD query this header before invoking Tier 2 methods.

Terminology The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 when, and only when, they appear in all capitals.

Tier 1 Method:: A core AGTP method defined in Section 7.2, required for baseline AGTP compliance.
Tier 2 Method:: A standard extended AGTP method defined in this document, registered in the IANA AGTP Method Registry, available to any implementation but not required for baseline compliance.
Idempotent:: A method is idempotent if multiple identical invocations produce the same result as a single invocation. Non-idempotent methods MUST NOT be retried without explicit application-layer handling.

ACQUIRE Category Methods ACQUIRE methods retrieve data, resources, or state without modifying it. Agents use ACQUIRE methods to observe, locate, and extract information from internal or external sources. All ACQUIRE methods are idempotent unless noted.

FETCH Purpose: Retrieve a specific resource by identifier. Distinguished from QUERY (which expresses an information need without specifying a location) by targeting a known resource at a known address. Use case: An agent retrieves the current version of a contract document by its document ID before passing it to ANALYZE. Parameter Required Description resource_id MUST Identifier or URI of the resource to retrieve format MAY Requested response format version MAY Specific version of the resource to retrieve if_modified_since MAY ISO 8601 timestamp; return only if modified after Response: Resource content with metadata. Idempotent: Yes. Error codes: 404, 403, 408.

SEARCH Purpose: Execute a structured search query against a data source and return matching results. Distinguished from QUERY by accepting structured query syntax (field filters, range constraints, sort order) rather than natural language intent. Use case: An agent locates all purchase orders above $50,000 in pending status, sorted by submission date. Parameter Required Description query MUST Structured query expression or filter object scope SHOULD Data sources or indices to search limit MAY Maximum number of results to return offset MAY Pagination offset sort MAY Sort field and order Response: Result set with pagination metadata. Idempotent: Yes. Error codes: 400, 422.

SCAN Purpose: Enumerate or iterate over a collection of resources, potentially applying lightweight filters. Distinguished from SEARCH by prioritizing completeness over relevance ranking. Use case: An agent audits all agents in a governance zone by iterating over the full registry, page by page, to build a compliance report. Parameter Required Description collection MUST Identifier of the collection to scan filter MAY Simple filter criteria cursor MAY Continuation cursor from a prior SCAN response page_size MAY Number of items to return per page Response: Page of results with continuation cursor if more items remain. Idempotent: Yes. Error codes: 404, 408.

PULL Purpose: Retrieve pending items from a queue or stream. Consumes items from the source; the agent takes ownership of pulled items. Use case: An order-processing agent pulls the next batch of unprocessed orders from the fulfillment queue to begin packing instructions. Parameter Required Description source MUST Queue or stream identifier max_items MAY Maximum number of items to pull visibility_timeout MAY Seconds for which pulled items are hidden from other consumers Response: List of pulled items with item IDs for acknowledgment. Idempotent: No. Error codes: 404, 409.

FIND Purpose: Locate an agent, resource, or entity matching specified criteria. Distinguished from SEARCH by targeting agent or entity discovery rather than content retrieval. Use case: An orchestrator locates all available analyst agents in the partner governance zone that support the VALIDATE method. Parameter Required Description criteria MUST Structured criteria for the entity to find namespace SHOULD Registry or namespace to search within limit MAY Maximum results to return Response: List of matching entities with identifiers and metadata. Idempotent: Yes. Error codes: 404, 422.

ANALYZE Purpose: Perform observational analysis or pattern detection on a dataset or system state. Distinguished from COMPUTE methods such as SUMMARIZE or CLASSIFY by returning findings, patterns, and anomalies rather than transforming the input. ANALYZE does not modify state. Use case: An agent detects anomalous spending patterns in a quarterly expense dataset by analyzing transaction frequency and amount distributions against historical baselines. Parameter Required Description target MUST Dataset, system identifier, or inline data to analyze analysis_type SHOULD Pattern type: anomaly, trend, distribution, correlation time_range MAY ISO 8601 time window for time-series data sensitivity MAY Detection sensitivity threshold (0.0-1.0) explain MAY If true, include reasoning behind each finding Response: Findings document with detected patterns, anomaly indicators, and confidence scores per finding. Idempotent: Yes. Error codes: 400, 422, 503.

COMPUTE Category Methods COMPUTE methods process or transform information to produce a derived result. Agents use COMPUTE methods to analyze, classify, summarize, and generate outputs from existing inputs. COMPUTE methods are typically idempotent given the same input.

EXTRACT Purpose: Pull structured information from unstructured or semi-structured source content. Use case: An agent extracts party names, dates, and obligation clauses from an unstructured legal contract into a structured JSON schema. Parameter Required Description source MUST Content to extract from schema MUST Target structure for extracted data confidence_threshold MAY Minimum confidence for included extractions Response: Extracted data conforming to the declared schema, with confidence scores per field. Idempotent: Yes. Error codes: 400, 422.

FILTER Purpose: Apply criteria to a dataset and return only matching records. Use case: An agent filters a product catalog to items that are in-stock, priced under $200, and tagged with a specific category. Parameter Required Description data MUST Dataset to filter (inline or by reference) criteria MUST Filter expression output_format MAY Format for filtered results Response: Filtered dataset. Idempotent: Yes. Error codes: 400, 422.

VALIDATE Purpose: Check input data, a document, or a proposed action against a schema, policy, or rule set. Returns validation results but does not modify state. Use case: An agent validates an invoice payload against the accounts payable schema and business rules before submitting it for payment. Parameter Required Description target MUST Data, document, or action to validate schema SHOULD Schema or rule set to validate against strict MAY If true, treat warnings as failures Response: Validation result with pass/fail status, errors, and warnings. Idempotent: Yes. Error codes: 400, 422.

TRANSFORM Purpose: Convert data from one format, schema, or structure to another. Use case: An agent converts a vendor's proprietary order payload into the internal canonical order schema before routing to fulfillment. Parameter Required Description source MUST Data to transform source_format SHOULD Format of the input data target_format MUST Desired output format or schema mapping MAY Field mapping specification Response: Transformed data in the target format. Idempotent: Yes. Error codes: 400, 422.

TRANSLATE Purpose: Convert content between human languages. Use case: An agent translates product descriptions from English into French and German to prepare a multilingual catalog update. Parameter Required Description content MUST Text or structured content to translate source_language SHOULD BCP 47 language tag; auto-detected if absent target_language MUST BCP 47 language tag of desired output formality MAY formal or informal Response: Translated content with source and target language codes. Idempotent: Yes. Error codes: 400, 422.

NORMALIZE Purpose: Standardize data values to a canonical form (dates, phone numbers, addresses, currency amounts, units). Use case: An agent normalizes customer records ingested from three regional CRMs using different date formats, phone conventions, and address schemas into a unified canonical format. Parameter Required Description data MUST Data to normalize type MUST Normalization type: date, phone, address, currency, unit locale MAY Locale context for normalization Response: Normalized data with original and canonical forms. Idempotent: Yes. Error codes: 400, 422.

PREDICT Purpose: Apply a model or function to input data and return a predicted output or probability estimate. Use case: An agent predicts the likelihood of customer churn for each account in a segment, returning probability scores and top contributing factors for accounts above the risk threshold. Parameter Required Description input MUST Input data for the prediction model_id SHOULD Identifier of the model to use confidence_floor MAY Minimum confidence required to return a result explain MAY If true, include feature attribution in response Response: Prediction result with confidence score and optional explanation. Idempotent: Yes. Error codes: 400, 422, 503.

RANK Purpose: Sort or score a set of items by relevance, quality, or a declared criterion. Use case: An agent ranks a shortlist of job candidates by predicted role fit, ordering them for recruiter review. Parameter Required Description items MUST List of items to rank criterion MUST Ranking criterion or scoring function limit MAY Return only the top-N items Response: Ranked list with scores per item. Idempotent: Yes. Error codes: 400, 422.

CLASSIFY Purpose: Assign one or more items to categories from a known classification scheme. Distinguished from RANK (which scores and orders items) and PREDICT (which estimates future states) by assigning categorical labels to existing data. Use case: An agent classifies incoming support tickets into one of eight predefined categories to route them to the appropriate team. Parameter Required Description items MUST Items or data records to classify taxonomy MUST Classification scheme or label set to use multi_label MAY If true, each item may receive more than one label confidence_threshold MAY Minimum confidence for a label assignment Response: Classification result with assigned labels and confidence scores per item. Idempotent: Yes. Error codes: 400, 422.

CALCULATE Purpose: Perform numeric, logical, or financial computations on structured inputs. Distinguished from PREDICT (probabilistic) and EVALUATE (qualitative comparison) by operating on deterministic mathematical or rule-based logic. Use case: An agent calculates the total cost of a procurement order including applicable taxes, shipping fees, and bulk discount rules. Parameter Required Description expression MUST Computation to perform, as a structured formula object or registered formula ID inputs MUST Named input values for the computation precision MAY Number of decimal places in the result currency MAY ISO 4217 currency code for financial computations Response: Computation result with inputs echoed, formula applied, and output value. Idempotent: Yes. Error codes: 400, 422.

EVALUATE Purpose: Compare a target against benchmarks, rules, standards, or criteria and return a qualitative or scored assessment. Distinguished from VALIDATE (pass/fail against a schema) by returning a graded assessment with explanatory context. Use case: An agent evaluates a vendor proposal against a weighted scorecard covering price, delivery timeline, compliance posture, and references, returning a composite score and narrative rationale. Parameter Required Description target MUST Item, document, or entity to evaluate criteria MUST Evaluation criteria or scorecard definition weights MAY Relative weights for each criterion rubric MAY Scoring rubric mapping values to qualitative labels Response: Evaluation result with per-criterion scores, composite score, and narrative rationale. Idempotent: Yes. Error codes: 400, 422.

GENERATE Purpose: Produce textual, structured, or code output from a source specification, dataset, or prompt. Distinguished from SUMMARIZE (which condenses existing content) by creating new content that did not exist in the source input. Use case: An agent generates API documentation from an OpenAPI specification, producing endpoint descriptions, parameter tables, and example payloads. Parameter Required Description source SHOULD Input specification, data, or context for generation output_type MUST Type of output: text, code, json, html, markdown format MAY Output format details (e.g., language for code generation) length MAY Approximate target length or size style MAY Style guidance: formal, casual, technical, neutral Security note: GENERATE with output_type: code MUST require human or governance review before passing to RUN. Implementations providing a pipeline from GENERATE to RUN MUST insert an explicit VALIDATE or approval step between them. Response: Generated content with output_type field. Idempotent: Yes (for identical inputs). Error codes: 400, 422, 503.

RECOMMEND Purpose: Generate a ranked list of suggestions, options, or actions tailored to a declared context, goal, and constraints. Distinguished from RANK (which scores a provided list) by generating the candidate set itself based on the agent's understanding of the context. Use case: An agent recommends three product accessories to a customer based on their purchase history, stated budget, and current browsing context. Parameter Required Description context MUST User, session, or situational context for the recommendation goal MUST What the recommendation is optimizing for constraints SHOULD Hard limits: budget, category, availability, exclusions limit MAY Maximum number of recommendations to return explain MAY If true, include rationale for each recommendation Response: Ordered list of recommendations with scores, rationale, and confidence per item. Idempotent: Yes. Error codes: 400, 422, 503.

TRANSACT Category Methods TRANSACT methods perform state-changing operations with external systems, records, or commitments. TRANSACT methods are not idempotent by default.

QUOTE Purpose: Pre-flight cost estimation for a proposed method invocation. The requesting agent submits a proposed method call; the server returns a cost estimate without executing the method. Servers supporting Budget-Limit SHOULD implement QUOTE. Use case: An agent estimates the token cost of a large-document SUMMARIZE operation before committing, to verify it stays within the session budget. Parameter Required Description method MUST The AGTP method for which a cost estimate is requested parameters MUST The parameters that would be passed to that method budget_units SHOULD Units in which to express the estimate Response: Cost estimate in Cost-Estimate response header and response body, with confidence range. Idempotent: Yes. Error codes: 400, 404, 422.

REGISTER Purpose: Create a new record, entity, or subscription in a target system. Use case: An onboarding agent registers a new employee in the identity management system, the access control system, and the payroll platform as three sequential REGISTER calls within a single session. Parameter Required Description entity_type MUST Type of entity to register data MUST Registration data idempotency_key SHOULD Client-provided key for duplicate detection Response: Registration receipt with new entity identifier. Idempotent: No (use idempotency_key for safe retry). Error codes: 409, 422.

SUBMIT Purpose: Deliver data, a document, or a work item to a processing system or queue for handling. Use case: An agent submits a completed expense report to the finance system's approval queue for human review. Parameter Required Description target MUST Destination system or queue payload MUST Data or document to submit priority MAY Submission priority callback MAY AGTP endpoint for delivery confirmation Response: Submission receipt with tracking identifier. Idempotent: No. Error codes: 400, 409, 503.

AUTHORIZE Purpose: Approve permissions, credentials, or access for an entity, action, or resource. Distinguished from VALIDATE (which checks conformance) by issuing an active grant rather than a check result. Use case: An identity agent authorizes a contractor's access request for a restricted project repository, generating a scoped access token with a defined expiry. Parameter Required Description subject MUST Agent-ID, principal, or entity to authorize resource MUST Resource or action being authorized scope MUST Permissions being granted ttl SHOULD Time-to-live for the authorization in seconds conditions MAY Conditional constraints on the authorization Security note: AUTHORIZE MUST carry authorization:grant in the agent's Authority-Scope. The granted scope MUST NOT exceed the authorizing agent's own declared scope (the anti-laundering constraint from Section 7.2.7 applies to all authorization grants). 451 Scope Violation MUST be returned if either constraint is violated. Idempotent: No. Error codes: 403, 409, 451.

CANCEL Purpose: Revoke or reverse a previously scheduled or committed transaction. Distinguished from lifecycle operations (agent suspension or revocation) by targeting a specific transaction, booking, or reservation rather than an agent's registry state. Use case: An agent cancels a conference room booking on behalf of the principal, releasing availability and notifying other attendees. Parameter Required Description target_id MUST Identifier of the transaction, booking, or reservation to cancel reason SHOULD Structured cancellation reason notify_parties MAY If true, NOTIFY relevant parties on cancellation refund_policy MAY Refund handling: full, partial, none Response: Cancellation receipt with confirmation and any refund details. Idempotent: No (cancellation of an already-cancelled item SHOULD return 409 Conflict). Error codes: 404, 409, 422.

TRANSFER Purpose: Move ownership or custody of a resource from one principal or agent to another. Use case: An agent transfers custodianship of a finalized contract to the legal archive system, removing it from the active working directory and updating ownership records. Parameter Required Description resource_id MUST Resource to transfer from_principal MUST Current owner to_principal MUST New owner reason SHOULD Reason for transfer Security note: TRANSFER MUST verify that the requesting agent holds Authority-Scope for the resource type being transferred. 451 Scope Violation MUST be returned if not. Idempotent: No. Error codes: 403, 404, 409, 451.

PURCHASE Purpose: Execute a financial transaction to acquire a resource, service, or allocation. Use case: A travel agent purchases a confirmed airline seat after the principal approves the itinerary, carrying the principal's payment method identifier. Parameter Required Description item MUST Item or service being purchased principal_id MUST Principal authorizing the purchase amount MUST Purchase amount and currency payment_method SHOULD Payment instrument identifier confirm_immediately MAY Boolean; if false, creates a hold Security note: PURCHASE MUST carry payments:purchase in the agent's Authority-Scope. 451 Scope Violation MUST be returned if absent. PURCHASE MUST validate against the Budget-Limit header if present. Idempotent: No. Error codes: 403, 409, 451, 452.

SIGN Purpose: Apply a cryptographic signature to a document, assertion, or data artifact using the agent's or principal's signing key. Use case: An agent signs a finalized service agreement on behalf of the principal using the organization's governance key, producing a timestamped, non-repudiable signature record. Parameter Required Description payload MUST Data to sign key_id SHOULD Identifier of the signing key to use algorithm MAY Signature algorithm; defaults to implementation default Response: Signed artifact with signature metadata. Idempotent: No (signatures include timestamps). Error codes: 403, 422.

LOG Purpose: Write a structured record to an audit trail or operational log. Agents SHOULD use LOG for governance-significant events rather than embedding log data in other method payloads. Use case: A financial agent logs each step of a multi-stage wire transfer approval workflow as discrete LOG events, creating an audit trail for compliance reporting. Parameter Required Description event_type MUST Structured event category data MUST Event data severity SHOULD info, warning, error, or critical correlation_id MAY ID linking this event to a parent task or session Response: Log receipt with record identifier. Idempotent: No. Error codes: 400, 503.

PUBLISH Purpose: Make content or data available to a defined audience or channel. Use case: An agent publishes a finalized research summary to the organizational knowledge base, making it discoverable to all users with knowledge:read scope. Parameter Required Description content MUST Content to publish channel MUST Target channel or audience identifier format SHOULD Content format schedule_at MAY ISO 8601 timestamp for deferred publication Response: Publication receipt with content identifier and channel confirmation. Idempotent: No. Error codes: 400, 403, 409.

INTEGRATE Category Methods INTEGRATE methods connect, synchronize, or unify data and services across system boundaries. Agents use INTEGRATE methods to eliminate fragmentation across silos, align state across environments, and establish relationships between entities. The INTEGRATE category is distinct from TRANSACT (no external commitment or irreversible state change) and from COMPUTE (no transformation of content into a new analytical form). INTEGRATE methods concern structural alignment and relational connectivity.

MERGE Purpose: Combine two or more datasets, documents, or resources into a unified result, resolving conflicts according to a declared policy. Use case: An agent merges duplicate customer profiles detected across two acquired subsidiary databases into a single canonical record, applying a "most recently updated" conflict resolution strategy. Parameter Required Description sources MUST List of resources or inline data to merge strategy SHOULD Merge strategy: union, intersection, latest, manual conflict_resolution MAY Policy for conflicting fields Response: Merged result with conflict report if applicable. Idempotent: No. Error codes: 400, 409, 422.

LINK Purpose: Create a persistent association or relationship between two entities in a system of record. Distinguished from MAP (which defines structural schema correspondence) by creating a relationship record between specific instances. Use case: An agent links a user's enterprise SSO identity to their account in a third-party analytics platform, establishing a persistent cross-system identity association. Parameter Required Description source MUST Source entity identifier target MUST Target entity identifier relationship MUST Type of relationship metadata MAY Additional relationship attributes Response: Link record with relationship identifier. Idempotent: No. Error codes: 404, 409.

SYNC Purpose: Reconcile the state of a local resource with a remote authoritative source, aligning records bidirectionally or unidirectionally. Use case: An agent synchronizes the local product inventory cache with the warehouse management system, pulling delta changes since the last sync timestamp and pushing any local updates that occurred offline. Parameter Required Description resource MUST Resource to synchronize remote MUST Authoritative source URI direction SHOULD pull, push, or bidirectional conflict_policy MAY remote_wins, local_wins, or manual Response: Sync receipt with change summary. Idempotent: No. Error codes: 404, 409, 503.

IMPORT Purpose: Bring external data into the agent's operational context or a designated storage target from a non-AGTP-native source. Distinguished from FETCH (which retrieves a known resource by ID from an AGTP-native address) by ingesting from external systems. Use case: An agent imports a CSV export of contact records from a legacy CRM into the new system, resolving format differences and logging import statistics. Parameter Required Description source MUST URI or inline data to import target MUST Destination identifier within the agent's context format SHOULD Format of the source data conflict_policy MAY Behavior on conflict: overwrite, skip, merge Response: Import receipt with record count and any conflict resolutions. Idempotent: No. Error codes: 400, 409, 422.

MAP Purpose: Define a structural correspondence between two schemas, data models, or field sets. Distinguished from TRANSFORM (which applies a mapping to convert a specific payload) by producing a reusable mapping definition rather than executing a one-time conversion. Use case: An agent generates a field-level mapping between an external vendor's order schema and the internal canonical order schema, producing a reusable mapping document that subsequent TRANSFORM calls can reference. Parameter Required Description source_schema MUST Schema or data model to map from target_schema MUST Schema or data model to map to strategy SHOULD Mapping strategy: exact, semantic, custom unmapped_policy MAY Behavior for fields with no target: ignore, flag, preserve Response: Mapping document with per-field correspondence and confidence scores. Idempotent: Yes. Error codes: 400, 422.

CONNECT Purpose: Establish a conduit, session, or integration channel between two systems, services, or agents. Distinguished from LINK (which creates a record-level association) by establishing an active communication or data pathway. Use case: An agent establishes a streaming data connection between a sensor telemetry feed and the observability platform, configuring the channel parameters and returning a handle for subsequent operations. Parameter Required Description source MUST Source system or agent identifier destination MUST Destination system or agent identifier channel_type SHOULD Type of connection: stream, webhook, polling, event-bus config MAY Channel-specific configuration parameters ttl MAY Connection lifetime in seconds; persists until CANCEL if absent Response: Connection handle with connection ID and channel metadata. Idempotent: No. Error codes: 404, 409, 503.

EMBED Purpose: Insert one component, dataset, or agent capability into another as a nested or composed element. Used when an integration requires one system to host or expose the functionality of another within its own operational context. Use case: An agent embeds a third-party risk-scoring model's output into the organization's credit decisioning workflow as a named sub-component, making its scores available inline within decisioning records. Parameter Required Description source MUST Component, dataset, or capability to embed target MUST Container or context to embed into binding SHOULD Named reference or mount point within the target version MAY Specific version of the source to embed Response: Embedding receipt with binding reference and version. Idempotent: No. Error codes: 400, 404, 409.

COMMUNICATE Category Methods COMMUNICATE methods deliver signals, messages, or structured outputs to recipients. Agents use COMMUNICATE methods to push information, respond to incoming requests, and surface results to humans and systems.

ALERT Purpose: Send a high-priority, time-sensitive message to a recipient or group. Distinguished from NOTIFY (Tier 1, general-purpose async push) by signaling urgency and requiring acknowledgment handling if not acknowledged within a declared timeout. Use case: An infrastructure monitoring agent sends a critical alert to the on-call team when database latency exceeds the SLA threshold, carrying metric value, threshold, and recommended escalation path. Parameter Required Description recipient MUST Target Agent-ID, human endpoint, or group message MUST Alert content with severity and context severity MUST critical, high, or warning acknowledge_by SHOULD ISO 8601 deadline for acknowledgment escalation_path MAY Fallback recipient if not acknowledged by deadline Response: Alert delivery receipt with alert ID. Implementations SHOULD track acknowledgment state and trigger escalation on timeout. Idempotent: No. Error codes: 400, 404, 503.

BROADCAST Purpose: Disseminate information simultaneously to multiple recipients or a defined group. Distinguished from NOTIFY (targeted at a specific recipient) by addressing an audience rather than an individual and not expecting individual responses. Use case: An agent broadcasts a scheduled maintenance window notification to all registered subscriber endpoints across three governance zones. Parameter Required Description audience MUST Group identifier, zone, or list of recipient identifiers content MUST Broadcast payload channel SHOULD Delivery channel: agtp, email, webhook, sms expiry MAY Timestamp after which the broadcast should not be delivered Response: Broadcast receipt with message ID and delivery count. Idempotent: No. Error codes: 400, 403, 503.

REPLY Purpose: Provide a direct, traceable response to an incoming NOTIFY, ESCALATE, or QUERY that explicitly requested a reply. Creates a response thread linked to the originating task. Use case: A human-in-the-loop handler sends a REPLY to a pending ESCALATE, providing a decision and carrying the original escalation ID for thread continuity. Parameter Required Description in_reply_to MUST Task-ID of the message being replied to content MUST Reply content urgency SHOULD critical, informational, or background Response: Reply receipt. Idempotent: No. Error codes: 404, 400.

SEND Purpose: Deliver a message or payload to a recipient through a declared external channel. Distinguished from NOTIFY (AGTP-native async push) by targeting non-AGTP delivery channels. Use case: An agent sends an email confirmation to a customer's registered email address after completing a booking, using a declared template identifier. Parameter Required Description recipient MUST Channel-specific address channel MUST Delivery channel: email, webhook, sms, push content MUST Message content template_id MAY Template identifier for formatted delivery Response: Delivery receipt with channel-specific confirmation. Idempotent: No. Error codes: 400, 404, 503.

REPORT Purpose: Generate and deliver a structured summary or analysis document to a principal or system. Distinguished from NOTIFY (raw payload push) by producing a formatted output artifact with declared structure. Use case: An agent generates and delivers a weekly sales performance summary to the sales leadership distribution list in PDF format. Parameter Required Description report_type MUST Report category scope MUST Data scope or time range for the report recipient MUST Target principal or endpoint format SHOULD Output format: pdf, json, html, markdown Response: Report delivery receipt with document identifier. Idempotent: No. Error codes: 400, 422, 503.

ORCHESTRATE Category Methods ORCHESTRATE methods coordinate, sequence, and manage workflows, tasks, and agents across time and system boundaries. Agents use ORCHESTRATE methods to build composite execution flows, manage failure recovery, and direct work to appropriate handlers.

CHAIN Purpose: Link a defined sequence of AGTP method invocations into a composite workflow where each step's output may be used as input for subsequent steps. Distinguished from BATCH (which executes unrelated tasks in parallel) by enforcing sequential dependency between steps. Use case: An agent chains SEARCH, followed by ANALYZE, followed by REPORT into a single declared workflow for weekly competitor intelligence, where each step uses the prior step's output. Parameter Required Description steps MUST Ordered list of AGTP method calls with parameters on_failure SHOULD Behavior if a step fails: abort, skip, retry, escalate context_propagation MAY If true, each step's output is available to subsequent steps timeout MAY Maximum total execution time across all steps in seconds Response: Execution receipt with chain ID and per-step status. Idempotent: No. Error codes: 400, 408, 422.

BATCH Purpose: Group multiple independent AGTP method calls for concurrent or bulk execution, reducing round-trip overhead. Distinguished from CHAIN (sequentially dependent) by executing steps independently without output dependency. Use case: An agent batches twenty TRANSLATE calls for product descriptions into a single BATCH invocation, reducing latency from twenty serial round-trips to a single parallel execution. Parameter Required Description calls MUST List of independent AGTP method calls to execute execution_mode SHOULD parallel or sequential; default parallel partial_success MAY If true, return results for successful calls even if others fail Response: Batch result containing individual outcome per call. Idempotent: Conditional (depends on idempotency of component calls). Error codes: 400, 408, 422.

MONITOR Purpose: Establish ongoing observation of an agent, resource, or condition. Returns a subscription handle; the AGTP server delivers updates via NOTIFY when observed conditions change. Use case: An agent establishes a monitor on the behavioral trust score of a set of sub-agents, receiving NOTIFY updates when any agent's score drops below the declared threshold. Parameter Required Description target MUST Agent-ID, resource URI, or condition expression events MUST Event types to observe callback MUST AGTP endpoint for NOTIFY delivery threshold MAY Condition value that triggers notification interval MAY Polling interval in seconds if event-based delivery is unavailable Response: Monitor subscription receipt with subscription identifier. To cancel monitoring, send NOTIFY with event type monitor_cancel and the subscription identifier. Idempotent: No. Error codes: 404, 400.

ROUTE Purpose: Direct a task, message, or work item to the appropriate handler or agent based on declared routing criteria. Use case: An agent routes an incoming customer inquiry to the appropriate specialized handling agent based on topic classification, account tier, and declared availability of candidate handlers. Parameter Required Description payload MUST Item to route criteria MUST Routing criteria or rules candidates SHOULD List of candidate Agent-IDs or endpoints fallback MAY Default handler if no candidate matches Response: Routing decision with selected handler identifier. Idempotent: No. Error codes: 404, 422, 503.

RETRY Purpose: Re-attempt a previously failed AGTP method invocation using a prior Task-ID. Distinguished from a new invocation by carrying the original Task-ID for idempotency checking at the server. Use case: An agent retries a failed BOOK call after a 503 Unavailable, carrying the original Task-ID so the booking system can detect and suppress any duplicate if the original call was partially processed. Parameter Required Description original_task_id MUST Task-ID of the failed invocation delay MAY Seconds to wait before retrying max_attempts MAY Maximum total attempts including this one Response: New task receipt linked to the original task. Idempotent: Yes (for idempotent original methods); No for non-idempotent originals. Error codes: 404, 409.

PAUSE Purpose: Temporarily halt a scheduled or repeating workflow without terminating it. Distinguished from SUSPEND (Tier 1, which targets a session) by targeting a workflow or schedule record. Use case: An agent pauses a recurring data pipeline workflow during a maintenance window, setting a resume timestamp at the scheduled end of the window. Parameter Required Description workflow_id MUST Identifier of the workflow or schedule to pause reason SHOULD Reason for pause resume_at MAY ISO 8601 timestamp for automatic resumption Response: Pause receipt with workflow status. Idempotent: No. Error codes: 404, 409.

RESUME Purpose: Restart a paused workflow or a suspended session. Use case: An agent resumes a paused procurement workflow after the required human approval has been received, using the resumption nonce issued at PAUSE time. Parameter Required Description workflow_id MUST Workflow or session identifier resumption_nonce MUST (for sessions) Nonce issued at SUSPEND or PAUSE checkpoint MAY State override for resumption context Response: Resumption receipt with current workflow status. Idempotent: No. Error codes: 404, 408, 409.

RUN Purpose: Execute a named, registered procedure or automation script. Implementations MUST NOT accept free-form execution strings; the procedure MUST be identified by a registered procedure_id. Use case: An agent runs a registered data quality validation procedure against a freshly imported dataset, passing the dataset ID as input and receiving a structured pass/fail report. Parameter Required Description procedure_id MUST Registered identifier of the procedure to run input MAY Input parameters for the procedure timeout MAY Maximum execution time in seconds Security note: RUN MUST require activation:run in the agent's Authority-Scope. Free-form execution strings MUST NOT be accepted under any circumstances. Idempotent: No. Error codes: 403, 404, 408, 422, 451.

CHECK Purpose: Query the status or health of an agent, resource, workflow, or external dependency. Returns a structured status response. Use case: An agent checks the availability of all three downstream payment processors before initiating a purchase, using depth: shallow to minimize latency. Parameter Required Description target MUST Agent-ID, resource URI, or system identifier depth MAY shallow (reachability only) or deep (full dependency check) Response: Status document with health indicators per component. Idempotent: Yes. Error codes: 404, 408.

Method Summary Method Category State-Modifying Idempotent Key Constraints FETCH Acquire No Yes SEARCH Acquire No Yes SCAN Acquire No Yes PULL Acquire Yes No Consumes items FIND Acquire No Yes ANALYZE Acquire No Yes EXTRACT Compute No Yes FILTER Compute No Yes VALIDATE Compute No Yes TRANSFORM Compute No Yes TRANSLATE Compute No Yes NORMALIZE Compute No Yes PREDICT Compute No Yes RANK Compute No Yes CLASSIFY Compute No Yes CALCULATE Compute No Yes EVALUATE Compute No Yes GENERATE Compute No Yes code output requires review before RUN RECOMMEND Compute No Yes QUOTE Transact No Yes No execution REGISTER Transact Yes No Use idempotency_key SUBMIT Transact Yes No AUTHORIZE Transact Yes No Requires authorization:grant; scope subset only CANCEL Transact Yes No TRANSFER Transact Yes No Requires scope PURCHASE Transact Yes No Requires payments:purchase SIGN Transact Yes No LOG Transact Yes No PUBLISH Transact Yes No MERGE Integrate Yes No LINK Integrate Yes No SYNC Integrate Yes No IMPORT Integrate Yes No MAP Integrate No Yes Produces mapping definition; does not convert data CONNECT Integrate Yes No EMBED Integrate Yes No ALERT Communicate No No Acknowledgment tracking required BROADCAST Communicate No No REPLY Communicate No No SEND Communicate No No REPORT Communicate Yes No CHAIN Orchestrate Yes No BATCH Orchestrate Yes Conditional MONITOR Orchestrate Yes No ROUTE Orchestrate Yes No RETRY Orchestrate Yes Conditional PAUSE Orchestrate Yes No RESUME Orchestrate Yes No RUN Orchestrate Yes No No free-form strings CHECK Orchestrate No Yes

Security Considerations

PURCHASE Authorization The PURCHASE method carries financial consequences and MUST be subject to strict scope enforcement. Implementations MUST reject PURCHASE requests that do not carry payments:purchase in the Authority-Scope header with 451 Scope Violation. Budget-Limit validation MUST occur before execution; 452 Budget Exceeded MUST be returned if the purchase amount would exceed the declared budget.

AUTHORIZE Scope Constraint The AUTHORIZE method grants permissions to other entities and is subject to the same anti-laundering constraint that applies to DELEGATE in the Tier 1 core: the scope granted by an AUTHORIZE call MUST NOT exceed the authorizing agent's own Authority-Scope. Any implementation receiving an AUTHORIZE request where the grant scope exceeds the authorizing agent's declared scope MUST return 451 Scope Violation and MUST log the event.

RUN Method Safety The RUN method is the highest-risk Tier 2 method. Implementations MUST maintain a registry of permitted procedure_id values and MUST NOT execute procedures not in that registry. Free-form execution strings MUST be rejected. Each RUN invocation MUST be logged with the full procedure_id, input parameters, and executing Agent-ID.

GENERATE Code Output Safety When GENERATE is invoked with output_type: code, the resulting code MUST NOT be passed directly to RUN without human or governance review. Implementations providing a pipeline from GENERATE to RUN MUST insert an explicit VALIDATE or approval step between them.

MONITOR Callback Verification The callback parameter in MONITOR specifies an AGTP endpoint to receive updates. Implementations MUST verify that the callback endpoint is reachable and that the requesting agent has authority to receive notifications at that endpoint before establishing a monitoring subscription. Unverified callbacks are a potential exfiltration vector.

TRANSFER and Ownership Chain Integrity TRANSFER operations modify resource ownership and create audit obligations. Implementations MUST record the complete ownership chain for each transferred resource in the governance audit trail. The Attribution-Record for TRANSFER MUST include both from_principal and to_principal.

IANA Considerations This document requests registration of the following methods in the IANA AGTP Method Registry established by Section 9.2: Method Category Status Description FETCH Acquire Permanent Retrieve a known resource by identifier from an AGTP-native address SEARCH Acquire Permanent Execute a structured query against a data source using field filters and sort criteria SCAN Acquire Permanent Iterate over a collection for completeness; prioritizes coverage over relevance PULL Acquire Permanent Consume pending items from a queue or stream; agent takes ownership of pulled items FIND Acquire Permanent Locate agents or entities matching criteria in a registry or namespace ANALYZE Acquire Permanent Detect patterns, anomalies, or trends in a dataset without modifying it EXTRACT Compute Permanent Pull structured fields from unstructured or semi-structured source content FILTER Compute Permanent Return only records from a dataset that satisfy declared criteria VALIDATE Compute Permanent Check data or a proposed action against a schema or rule set; returns pass/fail TRANSFORM Compute Permanent Convert a specific payload from one format or schema to another TRANSLATE Compute Permanent Convert content between human languages NORMALIZE Compute Permanent Standardize data values to canonical form: dates, phones, addresses, currency PREDICT Compute Permanent Apply a model to input data and return a probability estimate or forecast RANK Compute Permanent Score and order a provided list of items by a declared criterion CLASSIFY Compute Permanent Assign categorical labels to items from a known classification scheme CALCULATE Compute Permanent Perform deterministic numeric, logical, or financial computation on structured inputs EVALUATE Compute Permanent Score a target against a weighted rubric; returns graded assessment with rationale GENERATE Compute Permanent Produce new text, structured data, or code from a source specification or prompt RECOMMEND Compute Permanent Generate a ranked candidate set tailored to a declared context and goal QUOTE Transact Permanent Return a cost estimate for a proposed method call without executing it REGISTER Transact Permanent Create a new record, entity, or subscription in a target system SUBMIT Transact Permanent Deliver a document or work item to a processing system or queue AUTHORIZE Transact Permanent Issue an active permission grant; scope granted must not exceed authorizing agent's scope CANCEL Transact Permanent Revoke or reverse a specific prior transaction, booking, or reservation TRANSFER Transact Permanent Move ownership or custody of a resource between principals PURCHASE Transact Permanent Execute a financial transaction; requires payments:purchase in Authority-Scope SIGN Transact Permanent Apply a cryptographic signature to a document or artifact LOG Transact Permanent Write a structured record to an audit trail for governance or compliance purposes PUBLISH Transact Permanent Make content available to a defined audience or channel MERGE Integrate Permanent Combine two or more datasets into a unified result with declared conflict resolution LINK Integrate Permanent Create a persistent association between two specific entity instances SYNC Integrate Permanent Reconcile local and remote resource state bidirectionally or unidirectionally IMPORT Integrate Permanent Ingest data from a non-AGTP-native external source into the agent's context MAP Integrate Permanent Define a reusable structural correspondence between two schemas or data models CONNECT Integrate Permanent Establish an active communication channel or data pathway between two systems EMBED Integrate Permanent Insert a component or capability into another system as a named sub-component ALERT Communicate Permanent Send a high-priority, time-sensitive message requiring acknowledgment BROADCAST Communicate Permanent Disseminate a message simultaneously to a group or zone without expecting replies REPLY Communicate Permanent Provide a traceable response to a prior NOTIFY, ESCALATE, or QUERY SEND Communicate Permanent Deliver a message through an external channel: email, webhook, SMS, or push REPORT Communicate Permanent Generate and deliver a structured summary document to a principal or system CHAIN Orchestrate Permanent Execute a sequence of method calls with output-to-input dependency between steps BATCH Orchestrate Permanent Execute multiple independent method calls concurrently to reduce round-trip overhead MONITOR Orchestrate Permanent Establish ongoing observation of a resource or condition; delivers updates via NOTIFY ROUTE Orchestrate Permanent Direct a task or message to the appropriate handler based on declared routing criteria RETRY Orchestrate Permanent Re-attempt a failed invocation using its original Task-ID for idempotency checking PAUSE Orchestrate Permanent Temporarily halt a scheduled or repeating workflow without terminating it RESUME Orchestrate Permanent Restart a paused workflow or suspended session using a resumption nonce RUN Orchestrate Permanent Execute a registered procedure by ID; free-form execution strings are prohibited CHECK Orchestrate Permanent Query the health or availability of an agent, resource, or external dependency