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 adds useful context about billing cost and the returned data fields, but omits pagination, result limits, rate limits, auth requirements, and ordering. This is a clear gap for a search endpoint.

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 short sentences, front-loaded with purpose, then returned data, then cost. No filler or redundant restatement of schema fields; 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 simple two-parameter search tool the description is adequate, but it is not complete: it lacks pagination/result-limit information, rate limits, auth notes, and output structure details. It covers the core purpose, return content, and base cost, which are the most immediately needed facts.

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 schema already fully documents query and get_sentiment. The description mentions 'keyword' but adds little beyond the schema, and does not clarify operational details like pagination or surcharge amounts.

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?

Description states a specific resource (Threads posts) and action (keyword search), and enumerates returned content types. It differentiates from sibling tools like search_threads_users and threads_user_posts by confirming this searches posts by keyword rather than by user.

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 usage for keyword-based Threads post search, but it does not explicitly mention when to use this tool versus related siblings such as search_threads_users or threads_user_posts. No exclusions or alternatives are provided, leaving routing largely to inference.

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