search_comments

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

Beyond the readOnlyHint and idempotentHint annotations, the description discloses important behavioral traits: the Arctic Shift caveat that 'score and num_comments on anything newer than that are placeholders (usually 1 and 0) - never report them as real counts.' It also notes that keyword search is the slowest endpoint. This adds significant value 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?

The description is three paragraphs with zero filler. The first sentence establishes purpose, the second gives usage advice, and the third presents a critical caveat. Every sentence earns its place and the structure is logical and 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 the high parameter count (12), rich schema descriptions, and no output schema, the description is remarkably complete. It covers search dimensions, performance trade-offs, and data-quality caveats. The raw field's schema description plus the caveat about score/num_comments indirectly inform the output format, making further explanation unnecessary.

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 schema covers all 12 parameters with descriptions, so baseline is 3. The description adds extra semantics: 'With author alone this doubles as user comment history' clarifies the author parameter, and pairing body with subreddit/author/date range provides practical constraints not fully stated in the schema. This lifts it above baseline.

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's function: 'Find comments by subreddit, author, keyword, post or date range.' This is a specific verb ('Find') plus a resource ('comments') with enumerated search dimensions, which distinguishes it from sibling tools like search_posts and get_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?

The description provides explicit usage guidance: 'With author alone this doubles as user comment history' and 'Comment keyword search is the slowest endpoint - pair body with a subreddit, an author or a date range.' This tells the agent when to use the tool and how to optimize queries, including performance considerations.

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