Upload media

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

The description adds behavior beyond the annotations: 'Nothing is posted' clarifies the side effect, the 30-day retention states persistence, and 'one call per file' sets a batching constraint. These are meaningful operational details even though annotations already mark it as a non-destructive write.

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 short sentences, front-loaded with the core action and return, followed by sequencing, side-effect clarification, and retention. No sentence is redundant and the most important information comes first.

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?

With no output schema, the description still tells the agent what the call returns ('get its id') and how to use that result in publish_post. Combined with the detailed file schema and annotations, there are no material gaps for 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 file parameter's path/URL forms, size limits, and formats are already documented. The description still adds value by clarifying one image or video per call and that the result id is passed to publish_post media, which the schema does not state.

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 states a specific verb and resource ('Upload one image or video'), clarifies the return ('get its id'), and distinguishes the tool from publish_post by explaining the two-step flow. An agent can immediately tell this is the media-staging step rather than the publishing step.

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?

It explicitly says to use the tool ahead of publish_post, for videos and other large files, one call per file, and then pass the ids into publish_post media. That gives both the sequencing and the alternative delivery path without requiring inference.

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