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

With no annotations provided, the description carries full responsibility and does an excellent job. It discloses that RAW mode triggers the server to internally compute e = SM3(ZA || M) before verification, while DIGEST mode performs no implicit SM3 and directly verifies the provided digest. It also specifies the fixed signature format and the boolean output, giving complete insight into the tool's behavior.

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 well-structured with clear labels for parameters, output, and workflow. While it is longer than a simple two-liner, the complexity of the two-mode behavior justifies the length. The core purpose is front-loaded in the first sentence, and the bullet-style formatting improves readability. Some redundancy with the schema exists, but it remains tightly organized.

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?

The tool has 5 parameters and no output schema, yet the description compensates fully. It states the output is 'verified (bool)' explicitly, covers all parameters with mode-specific explanations, and provides a complete workflow reference. For a cryptographic verification tool with this level of complexity, the description is exceptionally complete.

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%, setting the baseline at 3. The description significantly enhances the schema by explaining the exact hex length requirement for DIGEST mode (64 hex characters for a 32-byte SM3 digest), the internal transformation e = SM3(ZA || M), and the critical constraint that sign_raw_data_mode must align with the signing mode. These details add substantial practical meaning beyond the parameter titles.

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 starts with 'SM2 公钥验签' (SM2 public key verification), clearly stating the tool's specific action and resource. It distinguishes itself from sibling tools like sm2_sign and sm2_encryption by mentioning the complete flow 'generate_sm2 → sm2_sign → sm2_verify', placing it definitively as the verification step.

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?

The description explains the two operating modes (RAW and DIGEST) and explicitly warns that sign_raw_data_mode must match the mode used during signing. It also notes that DIGEST mode is semantically consistent with KMS/ECC/RSA DIGEST mode, providing comparative guidance. The '完整流程' line gives a clear usage sequence, though it doesn't explicitly state when to avoid this tool in favor of alternatives.

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