usm/mcp-validate

MCP validate tool — validates a .usm file by path or inline YAML content against the v1 JSON Schema.

Intent

Agents modifying .usm files need to validate their changes before writing. The validate tool checks a file path or inline YAML string against the schema, returning valid/errors without the agent needing to call the CLI.

Flows

Validate by path (validate-path)

Agent validates an existing .usm file

1. get → file path
2. parse → YAML content
3. observe → validation result (valid + errors)

Contracts

validate-inline-or-path

Validate must accept either a file path or inline YAML content

Acceptance criteria:

• [ ] Returns { valid, errors } structure
• [ ] Errors include path and message
• [ ] File-not-found returns valid: false

Tests

validate-valid-path

Given:

• valid_usm_file: true

Then:

• assertion: result.valid is true

validate-inline

Given:

• inline_yaml: "summary: too short"

Then:

• assertion: result.valid is false
• assertion: errors list non-empty

Implementation

• Primary: src/mcp/validate.ts
• Test code status: none

See Also

• usm/cli-validate