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

Annotations declare readOnlyHint=false and destructiveHint=false, so the agent knows it's a non-destructive mutation. The description adds real value beyond that: it clarifies 'Nothing is published' (resolving the write-hint ambiguity), discloses that the call 'Counts toward the account's daily AI limit', and details the return shape including the missing-platform case. Strong disclosure, though it doesn't explain auth or failure modes.

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?

The core purpose is front-loaded in the first sentence, followed by per-platform rules and return shape. It is dense and long, but with no output schema the return-format detail is not wasted. Slightly packed, but every sentence carries information.

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 fully carries the return-value burden: the exact { drafts: { <platform>: { text, title?, ... } } } shape, the { missing: [...] } case, and the conditional presence of thread and first_comment. Combined with the publication and daily-limit notes, an agent has everything needed to call and interpret it.

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%, so all four parameters are already documented in the schema and the baseline is 3. The description lists per-platform formatting behavior (character limits, hashtags, hooks) that relates to the 'platforms' argument but adds no per-parameter syntax or constraint detail beyond the schema. Baseline 3 is correct.

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 and resource ('Writes one draft per platform from a single idea') and immediately scopes it as a drafting tool with 'Nothing is published', which cleanly separates it from publishing siblings like post_to_social and schedule_post. The verb+resource are fully clear and the agent can distinguish it from alternatives.

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?

Usage is implied rather than stated: 'Nothing is published' suggests using this when you want drafts, and the thread/first_comment passages describe output conditions. However, no sibling tool is named as an alternative and no explicit when-to-use-vs-when-not guidance is given. Adequate but leaves the agent to infer the routing.

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