post_tweet_with_image

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

No annotations are provided, so the description must fully disclose behavior. It details the required file existence, supported formats, character limit, optional reply threading, return object fields, and even mentions the underlying API fallback. Doesn't explicitly state authentication or rate limits, but overall transparent about operation.

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?

Four sentences, each earning its place: purpose/usage, file constraints, character limit + threading option, return value and backend note. Front-loaded with the main action. No unnecessary words or repetition.

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 moderate complexity (3 params, no nested objects, output schema present), the description covers purpose, usage, parameters, and return. Missing details on error handling or rate limits, but sufficient for an agent to invoke correctly. Output schema supplements return info.

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% (all 3 parameters described in schema). The description adds value by explaining image_path as a filesystem path with supported formats and existence requirement, and clarifies that reply_to_tweet_id is a numeric ID for threading. This goes beyond the schema alone.

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 clearly states it posts a new tweet with an attached image, distinguishing itself from siblings like post_tweet (text-only) and search_tweets (search). The verb 'Posts' and resource 'new tweet with an attached image file' are specific and unambiguous.

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?

Explicitly states when to use ('when the LLM needs to publish a status update that includes a photo...') and implies when not by mentioning alternatives (post_tweet for text-only). Also explains optional reply_to_tweet_id for threaded context. Lacks explicit rate limits or prerequisites, but provides clear context.

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