Canonical: https://agentmasterdata.com/agent-guide DISCOVER · EVALUATE · REQUEST # A first request your agent can reason about. Inspect the contract for free. Check availability, scope and cost. Accept results only when their evidence fits the task. Paid API live · this page does not check availability. These are pinned API contracts and connection instructions, not a live-service demonstration. The website makes no API calls and processes no payments. [Discovery JSON](https://agentmasterdata.com/agents.json)[Dataset JSON](https://agentmasterdata.com/datasets.json)[Tool contracts](https://agentmasterdata.com/tools.json)[API reference](https://agentmasterdata.com/api-reference) ## Discover the model and current availability Connect an MCP client to `https://api.agentmasterdata.com/mcp`. The API’s current product identity is **Trusted Master Data MCP**. Start with `get_master_data_schema` using `{}`; it is free. The seven tool descriptions below are copied verbatim from the pinned product contract. ``` curl 'https://api.agentmasterdata.com/mcp' \ -H 'Content-Type: application/json' \ -H 'Accept: application/json, text/event-stream' \ -H 'MCP-Protocol-Version: 2026-07-28' \ -H 'Mcp-Method: tools/list' \ --data '{"jsonrpc":"2.0","id":1,"method":"tools/list"}' ``` Read `_meta["com.agentmasterdata/availability"]` on every tool: `available`, `reason`, and `price_ids`. Check availability again before execution; a tool’s general availability does not prove coverage for a particular request. The equivalent free REST starting points are: ``` curl 'https://api.agentmasterdata.com/v1/master-data/schema' curl 'https://api.agentmasterdata.com/readyz' ``` `/readyz` can return HTTP 200 with `data_version: null` and `payments_enabled: false`. Its `counts` and optional `reference_counts` describe the loaded data families. `payments_enabled` is a deployment capability, not a per-tool or per-record permission. The pinned schema may say `unpublished` and contain empty coverage; never infer an available dataset from model vocabulary. ## Choose the narrowest tool ### `get_master_data_schema` Free discovery Free discovery tool. Get supported public master-data entity types, identifiers, searchable attributes, relationships, reference domains, coverage, and freshness. Use this first when an agent does not know the data model or valid filters. `GET /v1/master-data/schema` [Input schema ](https://agentmasterdata.com/contracts/schemas/tools/get_master_data_schema.input.schema.json)[Response contract ](https://agentmasterdata.com/contracts/master-data-schema.json) ### `search_master_data` Paid operation Paid x402 tool. Search trusted public master data for suppliers, locations, or organizations. Returns bounded golden-record summaries with match reasons, confidence, provenance, public-use status, freshness, and data-quality scores. Price ID: price.search.v1. Read masterdata://pricing before payment. `POST /v1/master-data/search` [Input schema ](https://agentmasterdata.com/contracts/schemas/tools/search_master_data.input.schema.json)[Response contract ](https://agentmasterdata.com/contracts/schemas/common/result-envelope.schema.json) ### `resolve_master_data_entity` Paid operation Paid x402 tool. Match incomplete or conflicting public supplier, location, or organization attributes to trusted master-data candidates. Returns explainable match evidence and never silently chooses an ambiguous entity. Price ID: price.resolve.v1. `POST /v1/master-data/entities/resolve` [Input schema ](https://agentmasterdata.com/contracts/schemas/tools/resolve_master_data_entity.input.schema.json)[Response contract ](https://agentmasterdata.com/contracts/schemas/common/result-envelope.schema.json) ### `get_master_data_golden_record` Paid operation Paid x402 tool. Retrieve one authoritative public golden record by stable record ID. Returns public attributes, identifiers, source-record lineage, survivorship evidence, freshness, relationships summary, and data quality. Price ID: price.record.v1. `GET /v1/master-data/entities/{entity_type}/{record_id}` [Input schema ](https://agentmasterdata.com/contracts/schemas/tools/get_master_data_golden_record.input.schema.json)[Response contract ](https://agentmasterdata.com/contracts/schemas/common/result-envelope.schema.json) ### `get_master_data_relationships` Paid operation Paid x402 tool. Get governed public relationships for one master-data golden record, such as supplier ownership, location hierarchy, or organization parentage. Returns direction, validity dates, provenance, and confidence. Price IDs by requested depth: price.relationships.depth-1.v1, price.relationships.depth-2.v1, or price.relationships.depth-3.v1. `GET /v1/master-data/entities/{entity_type}/{record_id}/relationships` [Input schema ](https://agentmasterdata.com/contracts/schemas/tools/get_master_data_relationships.input.schema.json)[Response contract ](https://agentmasterdata.com/contracts/schemas/common/result-envelope.schema.json) ### `get_reference_data` Paid operation Paid x402 tool. Get governed public reference data and controlled vocabulary values such as country, currency, unit of measure, industry, status, category, or code mappings. Returns codes, labels, definitions, validity dates, mappings, provenance, and version. Price ID: price.reference.v1. `GET /v1/reference-data/{domain}` [Input schema ](https://agentmasterdata.com/contracts/schemas/tools/get_reference_data.input.schema.json)[Response contract ](https://agentmasterdata.com/contracts/schemas/common/result-envelope.schema.json) ### `assess_master_data_quality` Paid operation Paid x402 tool. Assess the completeness, validity, consistency, uniqueness, and freshness of a master-data record or supplied attributes. Returns explainable issues, severity, affected fields, policy rules, and safe remediation guidance without changing data. Price ID: price.quality.v1. `POST /v1/master-data/data-quality/assess` [Input schema ](https://agentmasterdata.com/contracts/schemas/tools/assess_master_data_quality.input.schema.json)[Response contract ](https://agentmasterdata.com/contracts/schemas/common/result-envelope.schema.json) The common result schema constrains the envelope, not every operation’s data payload. We do not invent stricter output schemas where the upstream contract leaves data open. [Review pinned revisions and checksums](https://agentmasterdata.com/contracts/pins.json). ## Check price and permission before spending Discovery, schemas, readiness and price inspection are free. Six data operations require x402-capable client support. A plain MCP connection does not provide a wallet or authorization to spend. - Read [current prices](https://api.agentmasterdata.com/v1/pricing) and [payment discovery](https://api.agentmasterdata.com/.well-known/x402). Amounts, network, asset and recipient come from the deployment, not this website. - Read [data terms](https://api.agentmasterdata.com/legal/paid-public-data-terms), [attribution](https://api.agentmasterdata.com/legal/attribution) and [eligibility](https://api.agentmasterdata.com/eligibility/public-data-inventory). An unresolved or unavailable policy is a reason to stop and escalate. - Only within an authorized budget, obtain and inspect the request-specific 402 challenge. Confirm the quoted amount and payment parameters before your integration signs or submits payment. - Retain request and payment evidence. Do not blindly repeat payment after a timeout or uncertain settlement; reconcile with the integration’s documented idempotency and receipt handling. Relationship depth selects a price tier. Page limits and depth bounds are input constraints, not published rate quotas. Numeric rate and daily budget thresholds are not published; follow runtime refusals. ## Validate the answer and its evidence Outcome: Check `ok` and the operation-specific result. A successful HTTP response alone does not prove that the requested fact was found. Traceability: Retain `meta.request_id`, `meta.schema_version` and `meta.data_version`. Freshness: `meta.generated_at` dates the response, not the source. Inspect `meta.sources[].retrieved_at` when present; missing means unknown. Provenance: `meta.sources[]` identifies contributing `source_id` and `licence_id`. Permitted use: Evaluate `meta.public_use`, per-value terms when present, attribution and restrictions before reuse. Warnings: Preserve `meta.warnings`. Unknown validity is not known-active validity. Empty results may reflect filters, withholding or unavailable coverage. Payment: When present, inspect `meta.payment` and the `PAYMENT-RESPONSE` receipt. A receipt does not prove that the task succeeded. ## Handle refusal deliberately Response | Agent action | 400 / invalid arguments | Repair the input using the schema and error details. Do not repeat the same invalid request. | 402 / payment required | Evaluate the quote and authorization; pay only through a supported integration within budget. | 429 / rate or budget refusal | Respect `Retry-After`; stop or schedule a bounded retry within the caller’s policy. | 501 / payment_not_available | Do not attempt payment. Recheck discovery after the service changes. | 503 / service, payment or audit unavailable | Stop paid execution. Follow the returned code, retry guidance and any receipt; reconcile uncertain payment before retrying. | REST refusals use `application/problem+json`; MCP protocol refusals use JSON-RPC errors, with a payment challenge under `error.data.paymentRequired` when supplied. Operation-level errors in the common envelope include `code`, `message` and `retryable`, with optional invalid fields and suggested action. Do not assume every failure has the same wrapper. ## Measure a completed task Track task success, all HTTP attempts, elapsed time and settled cost by network and asset. Count retries and unsuccessful paid attempts. A discovery probe measures connection readiness only; it cannot prove paid retrieval, correctness or settlement. No production success rate, latency or price benchmark is claimed here. Define success before a run: choose an appropriate released dataset, submit valid bounded arguments, validate provenance and terms, and receive a result that meets the task’s acceptance criteria. The repository includes an opt-in free-discovery probe and an offline evaluator for agent-run evidence; neither submits a payment. ## For the humans supervising agents Agent Master Data supplies reference and master data to the agent you already use. Review the [release-scope catalog](https://agentmasterdata.com/#datasets), set permitted use and spending limits, and decide what evidence your workflow requires. The friendly logo and illustrations help identify the service; the API contracts determine how to use it. Questions or problems? Email [support@agentmasterdata.com](mailto:support@agentmasterdata.com). [Agent guide](https://agentmasterdata.com/agent-guide) · [Live API schema](https://api.agentmasterdata.com/v1/master-data/schema)