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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds valuable behavioral context by disclosing what the tool returns: 'ranked results with canonical and markdown URLs.' Since there is no output schema, this return-format detail is crucial. 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 two sentences with zero waste. The first sentence front-loads scope and return type; the second gives usage guidance. Every phrase earns its place, and it is appropriately sized for a search tool.

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 simple search tool with two parameters, strong annotations, and no output schema, the description is complete. It states what is searched, what is returned (including URL types), and when to use it. An agent has everything needed to invoke it correctly and interpret results.

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 input schema provides 100% coverage for both parameters: query has a description with examples, limit has min/max and a default. The tool description adds no additional parameter semantics beyond what the schema already conveys, 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?

The description states a specific verb ('keyword search') over a clear resource ('COTAL build log, documentation, and site pages'). It differentiates from siblings like cotal_get_post (single post), cotal_list_posts (listing), and cotal_overview by focusing on cross-content search. The purpose is unmistakable.

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 explicitly tells when to use the tool: 'Use it to find the page that answers a question before reading it.' This implies a workflow where search precedes reading, which is clear even though it doesn't name specific alternative tools or exclusions. The guidance is sufficient for an agent to select this tool appropriately.

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