Bluesky profile

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

The annotations already declare readOnlyHint and openWorldHint, so the description doesn't need to restate safety. It adds meaningful context by saying the profile is public, listing the exact fields returned, and positioning the tool as an existence check. It doesn't cover error behavior or rate limits, but those are minor given the annotation coverage.

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 short sentences with no filler. The first sentence front-loads the return fields, and the second provides the primary use case and sibling routing.

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 one-parameter, read-only profile lookup with no output schema, the description covers the return fields and the intended use context. The handle parameter is fully documented in the schema, so nothing an agent needs to invoke the tool correctly 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?

The schema already documents the only parameter, handle, with a format description and an example, so the description adds no new parameter semantics. With 100% schema description coverage, the baseline score of 3 is appropriate.

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 clearly identifies a public Bluesky profile lookup and enumerates the returned fields (display name, description, avatar, banner, counts), so an agent knows what resource is involved. It distinguishes itself from bluesky_posts by framing this as the existence-check/profile tool. It lacks an explicit action verb like 'get' or 'fetch', which keeps it just shy of a perfect score.

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?

It explicitly says to use this tool first to check whether a handle exists before calling bluesky_posts. This names the relevant alternative and gives a clear ordering rule. No other guidance is needed for a single-purpose profile lookup.

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