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

Goes well beyond the readOnlyHint/openWorldHint annotations: discloses quota cost ('each call counts against the daily search limit'), that no unlock is required, that names are returned without handles, the 0-1 matchScore range, and that the search is persisted and re-readable via list_searches/get_search. That is exactly the operational context an agent needs before spending a limited call.

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 core definition and packs cost, filtering, and output format into one dense but readable block with no filler. It is close to overloaded in a single sentence-chain, which slightly hurts scanability, but every clause carries information.

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 9-parameter read tool with no output schema, the description covers what an agent must know: input sourcing, quota implications, campaign-based exclusion, the shape of results (names, matchScore), and downstream persistence. Nothing essential to correct invocation 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 description coverage is 100%, so all nine parameters are already documented, and the description largely restates creatorId sourcing and campaignId exclusion rather than adding new semantics. It contributes only a small amount of extra framing (no handle/unlock needed) beyond the schema baseline.

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?

States a specific verb and resource ('Finds creators whose content is closest to one creator's, on the same platform') and scopes it to a similarity lookup keyed on creatorId. This is clearly distinguishable from search_creators, which is a keyword/discovery search rather than a nearest-neighbor lookup.

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?

Explains the entry condition clearly: 'pass the creatorId of a search result, no handle or unlock needed' and notes the campaignId exclusion path. It implies but never explicitly states when to prefer this over search_creators or get_creator, so there is a small gap in alternative routing.

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