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

With no annotations, the description carries the full burden. It discloses the 10-minute price lock, that the service is free, and what the user receives. It does not mention idempotency, side effects, or failure behavior, but the provided behavioral facts are meaningful and match the tool's purpose.

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?

Three short sentences, each earning its place: the core action and lock duration, the return payload, and a mandatory UX rule. No filler, fluff, or repetition of schema details. The most critical information is front-loaded.

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 description covers the essential return values and the locking behavior, which is sufficient given the schema's parameter documentation. It lacks explicit linkage to prerequisites (e.g., getting an offerId from list_offers) and does not describe error conditions, but for a pre-purchase quoting tool this is adequate. A slightly richer note on how the quoteId feeds into buy would make it 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 description coverage is 75%, so the baseline is 3. The description adds context about outputs (price, deliverables) but does not explain any specific input parameters, nor does it compensate for the 25% of undocumented schema fields. It neither significantly improves nor detracts from what the schema already 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-resource pair ('Lock a price') and scopes it to 'one purchase', clearly distinguishing it from siblings like buy or list_offers. It also states the return values (quoteId, exact USDC price, what will be delivered), leaving no ambiguity about the tool's function.

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 implies the tool's context with 'ALWAYS show the human the price and the recipient before buying', which signals quote's role as a pre-purchase step. It doesn't explicitly name alternatives or exclusions, but the sequential flow (quote before buy) is reasonably clear.

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