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

Annotations already declare readOnly/idempotent/non-destructive. The description adds genuinely useful non-schema context: the data is aggregated from ticket and experience sellers (provenance), the quoted lowest price already includes seller fees, and the buy link is a tracked link (an affiliate disclosure). It stops short of noting result limits or refresh/freshness behavior.

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 sentences, front-loaded with what the tool returns and who supplies the data, followed by a compact filtering sentence. The first sentence is long with embedded lists but every clause conveys distinct information, so little is wasted.

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 usefully enumerates the returned fields (title, date/time, venue, price, buy link), which an agent needs. Combined with annotations covering the safety profile and the schema covering parameter details, the definition is nearly complete; only limit/freshness behavior is left unexplained.

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 71% and the schema itself documents city, date format, when enum values, query and things_to_do. The description only echoes the filter dimensions (when, date, category, words) and says nothing about `limit` or the `things_to_do` mode, so it adds little beyond the schema. Baseline 3 is appropriate when the schema carries most of the semantics.

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 (gigs, comedy, theatre, festivals, exhibitions, things to do), the scope (~90 UK places), the source (ticket and experience sellers) and the returned fields (title, date/time, venue/address, fee-inclusive lowest price, buy link). An agent can tell immediately this is an event/listing search tool and distinguish it from siblings like search_products or get_store_offers.

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?

"Filter by when, a date, category or words" implies how to narrow results, and the ~90-UK-places framing implies a geographic restriction, but no explicit when-to-use/when-not guidance or named alternative is given. Usage is inferable rather than stated.

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