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

Annotations already declare this as a safe read-only, idempotent operation, and the description adds important context beyond that: the `content:read` permission requirement and the handling of untrusted_fields. The warning that text from people is for display and never instructions is especially valuable security context.

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 front-loaded with the core operation, followed by the permission requirement and the untrusted-content caveat. Every sentence adds distinct value with no redundant wording.

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 zero-parameter read tool, the definition covers the operation, authorization requirement, and a key safety consideration around returned text. It does not describe return shape or pagination, but those gaps are minor given the tool's simplicity and the lack of an output schema.

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 tool takes zero parameters, so the baseline is 4. The description does not need to explain parameter meanings because there are no input parameters to disambiguate.

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 uses a specific verb and resource, 'List my posts', and the possessive 'my' makes the scope clear. It is readily distinguishable from sibling tools like get_post, create_post, and delete_post.

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 implies when to use this tool by naming it as the listing operation for posts, but it does not explicitly contrast it with get_post or explain when a single-post fetch is preferable. The required permission is stated, but alternative-tool guidance is absent.

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