Get Friend

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

With no annotations, the description carries the full burden. It usefully discloses that returned details include balances and shared groups. However, it does not state side effects, failure behavior, or prerequisites such as whether the friendship must already exist, leaving a visible but moderate gap for a simple getter.

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 whole description is one front-loaded sentence containing the action, resource, and key return aspects. There is no repetition, filler, or restating of the schema.

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 single-parameter, low-complexity tool with an output schema, the description is nearly adequate: it previews the main return areas and the input is inferable. It is not fully complete because it omits any relation to sibling retrieval tools and does not clarify the meaning of user_id, but the tool's simplicity and output schema mitigate the omissions.

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%, and the tool description does not define user_id or explicitly say it is the friend's ID. The parameter name is suggestive, but the description adds no semantics beyond the schema's type and required flag, so it fails to compensate for the missing schema documentation.

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 opens with a specific verb 'Get' and names a specific resource, 'a friend's details,' further specifying 'including balances and shared groups.' This makes the tool's scope clear and helps separate it from sibling tools like get_friends and get_user, though it never explicitly contrasts them.

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 guidance about when to choose this tool over get_friends, resolve_friend, or get_user. The description only implies a single use case by naming the operation; it does not provide context, exclusions, or alternative routing.

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