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

Goes well beyond the annotations (which only cover read-only/idempotent/safety): it discloses the return shape (start times in local timezone, venue, summary, tags, ticket and source links, match reasons), the geographic coverage boundary and what happens outside it, and the pagination contract via next_offset. No annotation contradiction — openWorldHint=false is consistent with the explicit Bay Area-only coverage.

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-loaded with purpose, then progressively narrower guidance on query phrasing, structured params, returns, coverage, and pagination — a logical order. It is a dense block of text and the three quoted query examples are repetitive in form, but each sentence carries actionable content for a free-text search tool, so waste is limited.

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, zero-required, free-text search tool with no output schema, the description supplies everything an agent needs: what to put in `query`, when to use the structured filters instead, what a result contains, the coverage boundary, and how to page. Nothing material is left to inference.

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 already 89%, so the baseline is 3, but the description adds real meaning the schema does not: `query` may itself contain when, where, and who the search is for, with worked examples, and the 'who it is for' phrasing ('comedy this weekend for my parents, they hate crowds') is nowhere in the schema. It also restates the precedence of `from`/`to` over time in the query and the meaning of `near`/`place` as exact-knowledge alternatives.

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 ('Find events happening in a city') and immediately enumerates the domain (concerts, club nights, comedy, markets, festivals, classes, exhibitions), which separates it from the single-event `get_event` and the coverage-listing `list_coverage` without the agent needing either schema. The scope statement ('Covers the San Francisco Bay Area today') further pins down exactly what this tool does and does not return.

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 clear routing rules for the free-text vs structured parameters: pass plain words in `query`, use `from`/`to`, `place` or `near` 'when you already know them exactly', and continue with `offset` for more results. It also flags the failure mode (place outside the Bay Area returns not covered). It stops short of naming sibling tools or stating when-not to call this one, so it is clear context rather than full when/when-not/alternatives guidance.

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