recent_posts

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

Annotations already declare readOnlyHint/openWorldHint/destructiveHint=false, so the safety profile is covered. The description adds material context not in annotations: the per-post credit cost on X and the four return fields. No pagination or auth notes, so not a 5.

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 sentences, zero filler; the return-field list comes first and the cost warning follows immediately. Every clause carries information an agent cannot get from the schema or annotations.

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 simple 2-parameter read tool with no output schema, the description covers return shape, platform meaning and the credit caveat. Missing only default-limit behavior and whether results are paginated or ordered by recency.

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 50% (only platform is described, and that description merely restates the enum). The description compensates by mapping enum values to content types — threads/x = posts, itch = games, youtube = videos — and by giving the limit a practical meaning (small on X due to cost).

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 retrieval action plus the exact resource scope (Threads/X posts, itch.io games, YouTube videos) and enumerates the returned fields (id, date, shortened text, link). It doesn't name any sibling such as replies or post_stats to sharpen the boundary, so it falls short of 5.

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 one concrete usage instruction — keep limit small on X because each returned post costs credits — which is genuinely actionable. However, it never says when to prefer this over replies, post_stats or totals, so routing is left to inference.

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