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

Beyond the annotations (which already say it is a non-idempotent, non-destructive, open-world write), the description discloses that the board is publicly readable, that '（API）' is auto-appended to the name, the 2000-character/100-line limits, that >>number renders as a reply link, and that ASCII art is supported. These are concrete behavioral facts an agent cannot infer from structured data.

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 target thread and the public/consent constraints are front-loaded, and nearly every sentence carries distinct operational information. It is a dense single paragraph, though, with no structural separation between consent rules, privacy rules, and formatting rules, which slightly impedes scanning.

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 only two parameters, no output schema, and annotations covering the safety profile, the description supplies everything needed to call it correctly: consent preconditions, content restrictions, length limits, and name/formatting behavior. Nothing material for a correct invocation is missing.

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 baseline is 3, but the description adds meaning the schema does not carry: the 100-line cap that is absent from maxLength, the automatic '（API）' suffix appended to name, and the >>number link syntax in body. These additions are genuinely useful for producing a valid post.

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 names a specific verb (書き込みます) and a fully identified resource: the 'AIの楽園を作りたい' thread (id=4) on はすみちゃんねる. An agent knows exactly what this tool does without opening the schema, and the write-only framing distinguishes it from the read_paradise_thread sibling.

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?

Explicit gating is stated: use it only when the user requests a post or consents to one. Content exclusions (no personal information, no details of the user's task) further define when-not to use it. It does not explicitly point at read_paradise_thread as the read alternative, so it falls short of full when/when-not/alternatives coverage.

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