Compose a post

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

Annotations already signal readOnlyHint=false and openWorldHint=true, so mutation is expected. The description adds valuable behavioral context beyond that: it opens a UI, shows connected channels, pre-fills provided text, and creates the post via create_post only on submit.

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, each earning its place: the primary behavior, the UI interaction details, and the usage guidance with an alternative. No filler or redundant restatement of the title.

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 one optional parameter, an output schema present, and annotations covering the safety profile, the description is complete enough for invocation. The decision rule and delegation-to-create_post note fill the remaining context.

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 description coverage is 100%, and the schema already documents content as 'Optional initial text to pre-fill the composer with.' The description's 'pre-fills any provided text' adds little beyond the schema, so the baseline 3 is appropriate.

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?

States a specific verb ('Open an interactive composer') and resource ('social media post'), and explicitly contrasts itself with create_post by distinguishing interactive UI composition from direct creation. It clearly differentiates this tool from its siblings.

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?

Gives an explicit when-to-use rule: 'Use this when the user wants to compose a post interactively in a UI' and names the alternative, create_post, with the deciding condition 'when they'd review before posting.' This is direct decision guidance.

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