Grade a volunteer form

Form Grader (upload, URL, pasted, or form id). id and reportUrl (/tools/r/{id}) are present only for public grades. Saved-form grades omit id and reportUrl; owners use GET /api/v1/forms/{id}/grade. Anonymous grades omit restricted field labels from parsed; the score still counts them. The API key is optional. Anonymous calls need a Turnstile token in production. A failed check is 400 with error turnstile. A missing Turnstile configuration is 503. Dev and test skip verification. Keyless agents should use /mcp or POST /a2a instead of calling this route without a token. formId or formVersionId requires forms:read and does not use Turnstile. A key without forms:read is treated as anonymous.