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

Annotations indicate readOnlyHint=true, so the description need not explain safety. The description adds the notion that it evaluates 'similar events' and 'price', which supplements the schema. However, it does not disclose specifics like how similarity is determined, whether it uses forward-looking data, or what the returned metric represents (e.g., a hit rate percentage). No contradiction with annotations.

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?

The description is a single sentence, highly concise, and gets to the point immediately. It is appropriately sized for the tool's simplicity. No wasted words, though it could have added a bit more detail without losing conciseness.

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?

The tool has three parameters, an output schema is absent, and annotations are minimal (just readOnlyHint). The description is insufficient to fully understand the output format or how the hit rate is computed. However, given the tool's moderate complexity, the description covers the basic purpose. A higher score would require more details on computation and output.

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?

The schema description coverage is 100%, so all three parameters are documented in the schema. The description adds context by mentioning 'similar events' which implies eventType and lookbackQuarters play a role. But it does not further elaborate on parameter semantics beyond what the schema already provides. Since coverage is complete, a baseline of 3 is appropriate.

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 specific purpose: measuring how similar events affected price in the past. It clearly identifies the resource (historical event hit rate) and the action (analyze). It lacks some specificity about the exact output (e.g., a percentage or trend), but the core intent is clear and distinguishes it from siblings like get_event_risks.

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 description gives no explicit guidance on when to use this tool versus alternatives. It implies that the tool is for analyzing historical impact of events, but does not mention conditions or alternatives such as get_earnings_deepdive or get_event_risks. An agent would have to infer usage from context.

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