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

The annotations are all false (mutating, non-idempotent), so the description carries the burden of explaining behavior. It does so well: describes the caption-length-shaping logic ('tightest caption limit among the target platforms'), the return value (draft id), and the user-visible side effect (/drafts). No contradiction with 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?

Two lean, information-dense sentences. Front-loaded verb, clear flow from action → behavior → return value → next step. Zero wasted words.

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 correctly discloses the return value ('Returns a draft id') and the user-facing effect ('appears under /drafts for the user to review'). Combined with perfect schema coverage and simple flat params, this is complete for an agent to invoke correctly.

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 a 3 is the baseline for params alone. The description meaningfully connects the 'platforms' param to the caption-length-ceiling behavior and 'content_hint' to the generation input, adding semantic richness the enum/schema fields don't express.

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?

Uses specific verbs tied to a resource ('Compose a caption'... 'save it as a draft in sprkly') and adds meaningful detail about content-hint-driven generation and caption-limit shaping. The '/drafts' location distinguishes it from sibling scheduling tools like sprkly_schedule_post.

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?

Clearly frames a drafting workflow (compose → save → user reviews under /drafts) that differentiates it from schedule/delete siblings. However, it doesn't explicitly state when NOT to use it or name alternatives, leaving the exclusion implicit.

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