Tools MCP and External Integration
Tool Schema Validation — References
Tool schema validation › References
The schema language and the surrounding specifications that validation errors, paths, and semantic formats are expressed in.
The schema language
- JSON Schema — the specification site, covering the current draft, the keyword vocabularies, and the distinction between assertion and annotation keywords that decides whether a declared format is enforced at all.
- RFC 8259: The JavaScript Object Notation (JSON) Data Interchange Format — what a conforming document is, including the number-precision and duplicate-name questions that a validator alone does not settle.
- OpenAPI Specification — a widely implemented profile of schema usage for describing operation parameters and responses, and a useful catalogue of which constructs tooling reliably supports.
Addressing a failure
- RFC 6901: JavaScript Object Notation (JSON) Pointer — the path syntax most validators report errors against, and the thing that has to be translated before a model can act on the message.
- RFC 9535: JSONPath: Query Expressions for JSON — a standardised query syntax for selecting within a document, useful where a constraint concerns a set of positions rather than one.
- RFC 9457: Problem Details for HTTP APIs — a conventional envelope for returning a machine-readable failure type alongside a human-readable explanation, including extension members for per-field detail.
Semantic formats
- RFC 3339: Date and Time on the Internet: Timestamps — the timestamp profile the date-time format keyword refers to; the offset and leap-second rules are where emitted values most often go wrong.
- RFC 3986: Uniform Resource Identifier (URI): Generic Syntax — the grammar behind the URI-shaped format keywords.
- RFC 9562: Universally Unique IDentifiers (UUIDs) — the current specification for the identifier format most frequently declared and most frequently hallucinated.
No verified reference is recorded for which schema constructs a given model runtime actually enforces, or for measuring argument-level error rates in production agent traffic. The first is vendor documentation that changes per release; the second has no published methodology.