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

Annotations already declare readOnly/openWorld/non-destructive/idempotent=false, and the description adds real value beyond them: output cardinality ('up to 5 real, current products with a reason for each'), grounding method ('live web search'), and cost ('FREE: no credit is taken'). It stops short of covering failure modes (e.g. what happens with a vague instruction or how exclusions from prior results interact), so it is strong but not exhaustive.

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?

Front-loads the action, then inputs, outputs, cost, and sibling routing in a tight package. Every clause does work — the cost note and the charting/search routing are both decision-relevant, so no sentence is padding.

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 and only three parameters, the description carries the return-value burden and does so ('returns up to 5 real, current products with a reason for each'), plus grounding, cost, and when to call it. An agent has everything needed to invoke correctly.

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 the baseline is 3, but the description adds semantic framing the schema lacks: it explains the pairing of 'a vague or wrong target' with 'what the user wants instead' and enumerates instruction types (model, version, capability, market) with examples. It clarifies intent-shape rather than just restating field names.

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?

Specific verb ('Look again at one target from a search') plus explicit scope ('It refines one row'), and it names the contrasting sibling: 'to screen a whole market for a patent, use claimhit_search.' An agent can distinguish this from every sibling without opening a schema.

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?

Gives a concrete when-to-use ('Use it before charting, to chart the right thing') and an explicit exclusion/alternative ('It refines one row; to screen a whole market for a patent, use claimhit_search'). Nothing is left to inference.

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