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

Annotations already declare idempotent=true, destructive=false and openWorldHint=true; the description's main added value is disclosing the payment gate ('Paid x402 / X-Bazaar-Key: 0.01 USDC') and the specific claim set inspected. It does not state what the caller gets back (verdict shape, findings list) or how to supply the issuer/subject/expiration values, which is a meaningful gap for a validation tool with no output schema.

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?

One tight sentence, front-loaded with the billing prefix and then the concrete checks. Every clause earns its place; the paid-access tag is arguably noise but is operationally necessary.

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?

With no output schema, the description should signal what a lint run returns (pass/fail, flagged claims, severity). It instead stops at listing the inspected attributes, leaving an agent guessing about the result contract even though the input side is well covered.

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% for the single documented 'alg' parameter, so baseline is 3. The description does add that issuer, subject, and expiration are also examined, hinting the caller passes additional claims via additionalProperties, but it never explains how those are supplied — a small addition over the schema, not a substitute for it.

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-plus-resource construction ('Validate JWT signing algorithm... issuer/subject presence, and short-lived expiration window') that clearly scopes the tool to JWT claims security linting. The resource (JWT claims) is distinct from siblings like json_schema_lint or agent_card_lint. It stops short of naming an alternative, but the purpose is unmistakable.

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 security-lint framing implies you use it when auditing a JWT's alg/claims, but there is no explicit when-to-use, when-not-to-use, or named alternative among the many lint siblings. Guidance is present only by inference.

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