agent_verify_message

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

With no annotations, the description carries the full burden. It usefully discloses that verification is executed server-side on the relay (implying the envelope and signature are transmitted off-host), but says nothing about what happens on failure, error modes, or whether the relay must already know the sender_did.

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?

Two short sentences, front-loaded with the action and resource, with no filler. It is arguably too terse for a security-relevant tool, but nothing is wasted.

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?

No output schema and no annotations, yet the description never indicates the result shape (e.g., valid/invalid boolean, error on malformed input) or failure behavior. For a verification tool whose entire value is its verdict, this leaves a meaningful gap.

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 description coverage is 100%, so all three parameters (envelope, signature, sender_did) are already documented in the schema. The description adds no format or constraint detail beyond that, so baseline 3 applies.

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 ('check') and resource ('Ed25519 signature on a message envelope') and names the executor ('the relay'). It is distinguishable from nearby verification tools like agent_key_verify and verify_claim, though the description doesn't explicitly contrast 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?

No guidance on when to use this versus agent_key_verify or verify_claim, nor any prerequisites (e.g., must the sender be registered?). The agent is left to infer the use case from the purpose statement alone.

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