Resolve a handle to a DID

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

With no annotations provided, the description should disclose behavioral traits, but it only states that the tool looks up a DID. It does not mention error handling, handle format requirements, rate limits, or the response structure. The implication of a read-only lookup is present but not explicit, so this falls short of full transparency.

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 description is two short sentences, front-loaded with the primary action and no extraneous words. It efficiently conveys the core purpose and a use case.

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 one-parameter lookup tool with no annotations or output schema, the description provides a clear purpose and a usage hint. However, it omits potential errors, response format, and whether the handle is case-insensitive or requires a specific prefix. This is adequate for basic understanding but not complete.

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 input schema provides only a string parameter named 'handle' with zero description coverage. The description adds that it is a handle for which the DID is looked up, but it does not explain valid handle formats (e.g., '@username.bsky.social'), casing, or examples. Thus it adds minimal semantic value beyond the schema.

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 states the tool resolves a handle to a DID, using the specific verb 'look up' and identifying the resource (DID for a handle). It distinguishes from sibling tools by focusing on resolution rather than feeds or actions, and adds context that the DID is a permanent account id.

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 provides an implied context for use: 'Needed for some actions like following.' However, it does not explicitly state when not to use this tool or mention alternatives such as get_profile, which may also return a DID. This makes usage guidelines clear but not fully explicit, earning a 3.

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