ack_verify_jwt

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

No annotations are provided, so the description carries the full burden. It does disclose the core behavioral trait: it checks the signature against the issuer's DID and returns the decoded payload. However, it does not state what happens on invalid/expired tokens, whether network/DID resolution is involved, or whether there are any side effects, which leaves meaningful gaps for a verification tool.

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 sentences with no filler. The first sentence states the primary action and output; the second provides usage context. Information is front-loaded and every sentence earns its place.

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?

For a two-parameter tool with full schema coverage, the description covers the tool's purpose, output, and typical use case. However, there is no output schema and no explanation of error/failure behavior, which is important for a verification tool. The description is adequate but not complete enough to fully guide an agent through edge cases.

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 the schema already documents both parameters well, giving a baseline of 3. The description adds some context by mentioning the issuer DID in the signature-check step, which reinforces the 'issuer' parameter's purpose, but it does not introduce meaning beyond what the schema provides.

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 uses a specific verb and resource ('Verify a signed JWT') and states the output ('return its decoded payload'). It also mentions the signature check against the issuer's DID. However, it does not explicitly differentiate this from sibling verification tools like ack_verify_credential or ack_verify_payment_receipt, though the JWT focus makes the distinction reasonably clear.

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 provides explicit usage context: 'Use for verifying challenge-response tokens or any signed message from another agent.' This tells the agent when the tool is appropriate, but it does not mention when not to use it or point to alternatives among the siblings, so it falls short of full routing guidance.

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