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

No annotations are provided, so the description carries the behavioral disclosure burden. It goes beyond the schema by stating 'Flat 2 credits', 'Empty results and failures are never charged', and the cache behavior 'cache=true for a free 24h cache hit (default always fresh)'. It does not cover auth, rate limits, or error details, but the disclosed pricing and cache semantics are substantial.

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 content definition and is mostly compact. However, 'Flat 2 credits' and 'Costs 2 credits' are redundant, wasting a sentence on the same fact. Overall it is efficient but not perfectly polished.

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 3-parameter tool with no output schema and no annotations, the description covers the key operational facts: content returned, cost, failure no-charge, and cache usage. It is missing explicit routing guidance versus reddit_post_details/reddit_post_comments and some return-format details, but it is sufficient for basic correct invocation.

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?

Schema coverage is 100%, so the baseline is 3. The description adds operational meaning for the cache parameter ('free 24h cache hit') and reinforces flat pricing, but it does not clarify parameter-specific behavior such as how limit interacts with top comments. The schema already documents url, cache, and limit adequately.

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 the tool returns 'Written post text — title, body and top comments', which is a specific resource and content type. It also explicitly says 'Not a speech transcript', helping distinguish it from the many *_transcript sibling tools. However, it does not explicitly differentiate from reddit_post_details or reddit_post_comments.

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?

Usage is implied: use when you want a Reddit post's written text, not when you need a speech transcript. The phrase 'Not a speech transcript' provides an exclusion but no explicit alternative tool names or conditions such as 'use reddit_post_details for metadata' are given.

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