reddit_post_comments

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

Annotations already declare readOnlyHint=true and destructiveHint=false, establishing the safety profile. The description augments this by disclosing the return format (post plus threaded comments with author, body, score, replies) and pagination via an 'after' cursor. It does not discuss rate limits or auth, but the provided context goes beyond annotation basics.

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?

Three sentences, front-loaded with the core purpose, followed by return details and usage context. No filler or redundancy; every sentence earns its place.

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 single-parameter read-only tool with no output schema, the description covers what it returns, the pagination cursor, and the proper triggering context. It is self-sufficient for an agent to select and invoke it correctly.

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% since 'permalink' has a clear description with an example. The description additionally tells the agent to 'Pass the post's permalink from a prior result,' which adds provenance guidance beyond the schema's static definition.

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 action ('Fetch a single post and its comment tree by permalink') with specific resource and scope. It distinguishes itself from sibling tools like 'reddit_post' or 'reddit_search_comments' by specifying it returns the full comment tree, not just the post or search results.

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 provides clear context for when to use the tool: 'Use after finding a post via search/listing to read the full discussion.' It implies a workflow but does not explicitly state when not to use it or mention alternative tools, so it falls short of the full 5.

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