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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=false, so the safety profile is covered. The description adds genuinely useful output-behavior rules: attribution lines and an 'unclaimed' line must be relayed verbatim, and source links must stay attached to place names when passed on. It says nothing about auth/token requirements, result limits, or the shape of a returned place.

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 sentences, front-loaded with the core purpose before the output-relay rules, with little waste. The phrasing is conversational ('your person') but each sentence carries an actionable instruction.

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 four-parameter, open-world-flagged lookup with no output schema, the description should explain the access token, what 'interest' and 'limit' do, and roughly what a result contains. It covers only the query form and post-processing rules, so an agent cannot call it correctly without guessing at parameters.

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 0% across four parameters with no types or descriptions, so the description carries the full burden. It only implicitly covers 'town' via the query template; 'limit', 'interest', and especially 'token' (which appears to be an auth/access credential) are never mentioned, leaving an agent to guess.

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 concrete capability: answering 'where can I … in <town>' queries with sourced places, which tells an agent exactly what the tool returns (places plus source attributions). It does not differentiate from siblings such as fathom_find, capabilities_search, or places_verdicts, and the name 'knowledge_lens' is far broader than the places-lookup behavior described.

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 trigger condition is explicit and quoted: use this when the user asks a 'where can I … in <town>' question. That is a clear when-to-use signal. There is no guidance on when not to use it or which sibling to prefer for adjacent needs (general search, verdicts on places).

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