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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds two useful behavioral facts beyond the structured fields: results are public posts and the batch must contain 1-25 URIs. It does not disclose any auth, rate-limit, or ordering behavior.

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?

A single efficient sentence with no filler, and the key constraint (1-25 uris) is present up front. The wording is slightly garbled ('repeated uris query parameters'), which costs it a point.

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?

An output schema exists, so return values need not be described, and annotations cover the safety profile. Still, for a lookup tool sitting among many near-identical bluesky sibling tools, the description lacks the routing and format details an agent needs to call it confidently.

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 0% for the single uris parameter, so the description must compensate. It does add real meaning by clarifying that uris are post identifiers and that 1-25 of them are required, which the bare array-of-strings schema does not convey, but it stops short of explaining the URI format or null handling.

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 states a verb and resource ('Returns public posts') and identifies the input as uris, so the basic operation is graspable. However, the phrasing 'for 1-25 repeated uris query parameters' is awkward and it makes no attempt to differentiate from siblings like bluesky_post_thread or bluesky_author_feed, leaving the agent to infer scope.

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?

There is no indication of when to use this tool versus alternatives, no prerequisites, and no mention of the other bluesky post-fetching tools in the sibling list. The agent is given no routing guidance at all.

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