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

With no annotations, the description carries the disclosure burden and does a strong job: it warns that verified=false is the normal response for a mismatching signature/identity, and that only malformed input raises the 'SM9 verify failed' error. This is genuinely useful, though the phrasing 'verified=false 是成功响应' is slightly ambiguous and it does not describe the full output shape.

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?

The description is dense and mostly front-loaded, with the operation stated first and input constraints following. The repeated '[sm9_ibc] [sm9_ibc]' prefix is redundant but does not meaningfully harm readability.

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?

Given no output schema and no annotations, it covers the essential call context: required inputs, exact signature length, success-vs-error behavior, and the error code string. It omits explicit mention of what verified=true indicates, but the agent can infer the boolean semantics from the verification context.

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?

The schema already describes all four parameters at 100% coverage, so the baseline is 3. The description adds high-value constraints not in the schema: master_public_key_in_pem must be the key_kind=Sign public key and signature_in_hex must be exactly 104 bytes (208 hex characters).

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?

The description names a specific operation, 'SM9 标识验签（GM/T 0044）', and immediately scopes it by stating that verification only requires the master public key and signer identity. This makes it clearly distinct from sm9_sign and the other verify siblings even without explicitly naming them.

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?

It gives a clear usage context: use when verifying an SM9 identity signature with only the master public key and signer identity. It does not name alternatives or state when not to use it, so it stops short of a 5.

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