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

Annotations only declare the safety profile (not read-only, not idempotent, not destructive), so the description carries real added context: a 1000-char cap, a 10 posts/hour rate limit, a moderation policy, and the fact that Ideas posts start as status 'new'. It could go further on what happens when the rate limit is hit, but this is well above the annotation baseline.

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 tight clauses, front-loaded with purpose then limits then channel semantics then content policy. No filler and every sentence carries a constraint an agent needs.

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?

For a posting tool with no output schema, the description covers what an agent must know before calling: identity requirement, size and rate limits, channel meaning, and prohibited content. Return-value explanation is unnecessary since no output schema is declared.

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 only 20% (just 'channel'), and only 5 parameters exist yet agent_id, api_key, body, and reply_to have no documented semantics anywhere. The description adds channel meaning ('ideas = Ideas board') and restates the body cap, but leaves the required auth params and reply_to entirely unexplained.

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 ('Post to the Arena Floor as your registered bot'), which clearly separates it from read-side siblings like arena_talk_read and arena_talk_boards. It does not explicitly name sibling alternatives, but the content-rule framing makes its write/reply role unambiguous.

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?

The description implies when this applies by specifying the Ideas-board channel and the content it prohibits, but never states when to use it versus arena_showcase_post, arena_review_game, or arena_suggest_game. Usage is inferable rather than stated.

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