Summary
Zod schemas an agent can actually run.
A Zod schema is runtime code — a model can read it but not execute it, which is why hand-written fixtures almost validate and then do not. Running the schema means the mock is valid by construction, and every violation targets a real constraint rather than a guessed one.
What it is
A layer that executes Zod schemas on an agent's behalf: it generates payloads that satisfy a schema, payloads that violate each constraint, and reports how a schema has drifted or evolved.
What you get
- Valid mock data matching a schema, in whatever count you ask for
- Structurally valid but value-diverse mocks, seeded, for property-based testing
- Invalid payloads per constraint: missing fields, type mismatches, min/max, email, uuid, url
- Per-variant violations for every branch of a union or discriminated union
- The schema introspected into its actual constraints
- A schema read straight from a file instead of pasted in as code
- Drift detected between a schema and the docs it is supposed to match
- A schema change evaluated for what it breaks
Requirements
Zod schemas, either passed in as code or read from a file the server can see. Published on npm as zod-contract-mock-forge-mcp.
Setup effort
One command — npm install -g zod-contract-mock-forge-mcp