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

Annotations declare readOnlyHint=true and destructiveHint=false. Description adds that results are paginated, includes project-wide counts, and must follow nextOffset. No contradiction, adds useful behavioral context beyond 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?

Two concise sentences, no wasted words. First sentence states purpose and return structure, second explains pagination. Well front-loaded.

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?

Given output schema exists, description covers pagination, default limit, and return data outline. Could mention read-only nature but annotations already convey that. Adequate for a listing tool.

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?

Adds meaning beyond schema: default limit value, offset usage described as 'skip and follow nextOffset'. ProjectId not described but is a required UUID; overall adds value with 67% schema coverage.

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?

Description clearly states it returns a slimmed page of sources with total and counts, using specific verbs and resource. Distinguishes from sibling tools like betterpost_add_source and betterpost_remove_source by listing sources rather than modifying them.

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?

Provides clear pagination instructions using limit, offset, and nextOffset. Mentions default limit (50). Lacks explicit when-not-to-use or alternatives, but context is sufficient for a list endpoint.

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