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

With annotations declaring readOnlyHint=false, the description properly discloses the mutation: claiming is permanent, cannot be undone, stars are moved and never revert, and deleting the listing afterwards does not give stars back. It also discloses security-relevant behavior: other wallets are refused with specific error reasons, and the 'wallet_proof' must be valid for 10 minutes. The `_untrusted` marker for endpoint-provided fields is an extra behavioral disclosure beyond annotations.

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 but every sentence earns its place: preconditions, failure modes, irreversible effects, consequences for reviews, special-case handling (unreachable), rate limit, and untrusted field disclaimer are all packed into a single paragraph with clear logical flow. It front-loads the core action and the critical warning about irreversibility.

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 mutation tool with no output schema and two deep parameters, this description is complete. It specifies the proof format, time window, allowed/refused cases, consequences for reviews, rate limit, and what fields are untrusted. The only minor gap is the exact reply structure on success, but the description covers what matters for invoking correctly and interpreting the `_untrusted` fields. Nothing an agent needs to call this tool safely is missing.

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%, so a baseline of 3 applies, but the description adds meaning far beyond the schema. It defines what constitutes a valid wallet_proof (purpose, subject, signing key, validity window), and explains the semantic consequence of the listing_id parameter (claiming changes ownership, moves reviews/sales). The idempotency_key is contextualized with the general rule and the note that replies carrying secrets are shown once. This goes well beyond what the schema alone 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 states a specific verb ('Claim a listing we indexed') and resource (a listing), and clearly distinguishes this from the 40+ siblings by describing the exact action: prove control of the wallet the endpoint is paid to, and the listing becomes yours. It is unmistakably different from createListing, updateListing, and reportListing.

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 gives explicit when-to-use guidance: 'Read getReviews(listing_id) before you sign', explains that claiming cannot be undone, and clarifies when claiming is refused (conflict/already_claimed, too_many_reviews, not_found). It also notes that an unreachable listing can still be claimed and how to reactivate it with updateListing, which is a clear alternative tool reference.

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