get_user_info

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

With no annotations provided, the description carries the full burden. 'Look up' implies a non-destructive read operation, but it does not disclose error handling, authentication requirements, or exact return behavior (e.g., format, what happens if user not found).

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 a single, front-loaded sentence that states the core action and target resource without any filler. It is appropriately concise for a simple lookup tool.

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 simple scope (lookup by ID) and full schema coverage, the description is mostly complete. However, with no output schema, it does not explain the return format beyond 'display name', nor does it address error conditions or dependent operations.

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 descriptions cover 100% of parameters (user_id as 'User ID', chat_id as 'Chat context (optional)'). The tool description adds no additional information about parameter usage, formats, or dependencies, so baseline 3 applies.

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 uses a specific verb 'look up' and resource 'display name by user ID', clearly stating what the tool does. It distinguishes itself from sibling tools like search_contacts or list_profiles by focusing on a lookup by user 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 no guidance on when to use this tool versus alternatives such as search_contacts or list_profiles. It neither mentions context nor exclusions, leaving the agent to infer usage from the simple verb.

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