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

Annotations already cover safety (readOnly, openWorld, non-destructive), so the description rightly spends its words elsewhere: it discloses the return shape (extracted useful text per source, tagged with a source id [sN]) and a per-request call cap of 3. That is meaningful behavior beyond the structured fields, though it doesn't say what happens on failure or whether findings get stored on the document.

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?

Two compact sentences, front-loaded with purpose before the return format and the call limit. Minor waste: 'the useful text of each source' is slightly vague, and 'Up to 3 times per request' is appended without explaining what a 'request' scopes to.

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, the description supplies the one thing an agent most needs to know about results: they arrive as extracted source text keyed by [sN] ids, which supports later citation. Combined with the call budget and the subject scoping, an agent has enough to invoke it 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 schema already documents both parameters, including '1 to 4 concrete searches'. The description reinforces the targeting of queries ('THIS business, place or person') but adds no syntax, batching, or document_id semantics beyond what the schema states.

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 concrete verb ('Search the web') and a concrete target ('facts of THIS business, place or person'), then enumerates what that means (what it sells, address, phone, schedule, social media). The 'landing_' prefix and 'THIS' scope it to the current document's subject, which distinguishes it in spirit from deck_research/ads_research, but the description never names those siblings.

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?

Usage is only implicitly conveyed: 'THIS business, place or person' implies research on the document's subject, and 'Up to 3 times per request' sets a call budget. There is no statement of when to prefer this over deck_research or ads_research, nor any prerequisite (e.g. that document_id must be an existing landing document).

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