Verify CMS SignedData (the RFC 5652 verdict: signers, chains, time-stamps, revocation)

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly/idempotent/non-destructive, but the description adds far more: a negative verdict is valid:false with reasons, never an isError; isError is reserved for refused inputs (content supplied for an attached message, both content and contentDigest); the server never fetches CRLs or OCSP; and cacheability depends on pinning `at`. That is exactly the behavioral context an agent cannot infer elsewhere.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the core verdict statement, and every sentence carries distinct information despite the density. It is a single long paragraph with heavy parenthetical nesting, which for a 21-parameter tool is defensible but not maximally scannable.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return structure need not be described, and the description still covers the semantics of the verdict, error conditions, offline revocation posture, and caching. Nothing an agent needs in order to invoke this correctly is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3; the description still adds cross-parameter meaning the schema cannot express — that a detached signature without its content is invalid, that `contentDigest` covers the PDF /ByteRange case, that `atTimeStamp` judges each signer at its own verified TSA time, and that `intact` separates altered from untrusted. It does not touch all 21 parameters, so not a 5.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource — 'the one-call verdict on a CMS SignedData' — and enumerates exactly what the verdict covers (signed attributes, digests, signature, chain, time-stamps, revocation). The framing as a verdict tool cleanly separates it from inspection siblings like inspect_cms, which only decode.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives strong conditional guidance: pin `at` for reproducible verdicts, use `atTimeStamp` for long-term validation, `requireRevocation` to demand evidence, `content`/`contentDigest` for detached signatures, `verbosity:'summary'` for token-frugal calls. It never explicitly names when to prefer a sibling such as inspect_cms or verify_certificate_chain instead, so it stops short of full alternative routing.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.