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

Annotations already declare read-only, idempotent, non-destructive, closed-world behavior. The description adds useful behavioral context by specifying that per-network versions include caption, hashtags, YouTube title, status, link, and error, and that engagement metrics are latest and available once published. It does not cover not-found/error behavior, but beyond annotations this is solid.

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?

Single sentence, front-loaded with the returned data and no filler. The parenthetical list is dense but each item contributes to what the agent will receive.

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?

With no output schema, the description carries the return-value burden and does a good job enumerating text, media, per-network variants, and metrics. For a simple one-param read tool with safety annotations, this is complete enough; only error/empty-state behavior is unmentioned.

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?

Only post_id exists; schema coverage is 100% and its description already says 'The post id from list_posts.' The tool description adds no further parameter meaning, so baseline 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 names the resource and scope ('one post') and enumerates the returned content: full text, media, per-network versions, and engagement metrics. It never uses a retrieval verb or names list_posts as the source/alternative, so it is clear but not fully sibling-differentiating.

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?

It implies use for fetching a single post by describing single-post data, and 'once it is published' hints at the metrics precondition. But it gives no explicit when-to-use, when-not, or alternative such as list_posts, so guidance is only implied.

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