x_profile

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

No annotations are provided, so the description must fully disclose behavioral traits. It describes the tool as retrieving public data, which implies a read-only operation, but it does not mention any potential side effects, authentication requirements, rate limits, or what happens if the username is invalid. The minimal behavioral information earns a score of 2.

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 extremely concise, consisting of two short sentences that immediately state the tool's action and what it returns. Every word serves a purpose without redundancy. The structure is front-loaded with the verb, making the tool's function immediately clear.

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?

Given the tool's simplicity (one required parameter, no output schema, no nested objects), the description provides adequate context: it retrieves a profile and returns public details. However, it could be more complete by explicitly stating that only public profiles are accessible and what happens in error cases (e.g., username not found). The description is nearly complete for the tool's complexity, earning a score of 4.

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 for the single parameter 'username' is 100%, with the description already providing 'X username' in the schema. The tool description adds 'Returns public profile details for an X username', which reinforces the parameter's purpose but does not add new semantic meaning beyond the schema. The description's mention of return content (visible counts, profile media) is about the output, not the parameter itself. A 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 states 'Retrieve an X profile' and specifies that it returns public profile details including visible counts and profile media. The verb-resource combination is precise and distinguishes this tool from sibling tools like x_post or x_profile_posts, which deal with different aspects of X.

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 does not explicitly state when to use this tool versus alternatives, nor does it mention any prerequisites or exclusions. While the tool's purpose is clear, the lack of usage context (e.g., when to choose this over other social media profile tools) leaves room for ambiguity. A score of 3 is appropriate as it meets the minimum viable standard but lacks explicit guidance.

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