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

Annotations already declare readOnlyHint, idempotentHint and non-destructive, so the safety profile is covered. The description adds real context beyond that: it costs one call from the daily API quota, and it may return empty when market activity is sparse. It does not discuss staleness or how far the looksback default extends practically, but the added value is substantive.

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, no filler, front-loaded with what the tool returns and how it differs from a pitch. Cost and sparse-result behavior are placed last as operational notes, which is the right ordering.

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 carries the return-shape burden and does describe it (dated events plus the shared market themes they were matched on), along with cost and empty-result behavior. It is complete enough to invoke correctly, though it could say more about how adjacency/themes are determined.

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% and both parameters are documented in the schema, including the important note that company is the RECIPIENT and the 90-day default for lookback_days. The description adds no parameter-level detail beyond that, so the baseline of 3 applies.

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 resource and scope: recent activity (raised, hired, won contract, filed, expanded) among companies adjacent to a given company's market. This is clearly differentiated from the sibling point-queries like search_funding_rounds or search_executive_changes because it aggregates events by market adjacency rather than by a single event type. An agent can tell what it gets without opening the 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 an explicit situational purpose ("for opening outreach with a market update rather than a pitch") and a useful precondition about data volume ("returns few or no rows when little has happened"). It stops short of naming alternative tools or stating when not to use it, so it is clear context without explicit exclusions.

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