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

Annotations already declare readOnly=true, idempotent=true, and destructive=false. The description adds that it returns markdown content with specific fields (title, summary, date, author, full body), which provides context about the output behavior without contradicting the annotations. No side effects are implied, consistent 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 no redundancy. It states the purpose, the output format, and how to obtain the slug, all efficiently. No unnecessary words or ambiguity.

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 get-by-slug tool with a single parameter, the description is complete. It tells what it returns, how to get the slug, and the output format. No output schema is provided, but the description sufficiently describes the return value. Given the simplicity, nothing essential is missing.

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 fully covers the parameter with minLength, maxLength, and a description. The description adds a concrete example ('agi-summit-2026') that clarifies the expected format, which is helpful beyond the schema. Coverage is high, so the baseline is 3, but the example earns a 4.

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 clearly states it returns a single build-log post by slug, distinguishing it from list_posts (which likely lists all posts) and search (which finds posts). The verb 'returns' and the specific resource 'post' make the purpose unambiguous.

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 instructs to get slugs from cotal_list_posts or cotal_search, indicating when to use this tool after obtaining a slug. However, it does not explicitly state when not to use alternatives, such as 'use this instead of list_posts when you need full details of one post.' Still, the guidance is clear enough.

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