update_avatar

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

The description discloses the partial update behavior, which is a key behavioral trait, and implies modification. However, without annotations, it lacks details on authentication needs, rate limits, or error states. The partial update disclosure is useful but incomplete.

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 very concise: two sentences plus a parameter list, front-loaded with the primary action. Every sentence adds value without redundancy.

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 mutation tool with 3 parameters and an output schema, the description covers input semantics but does not describe the return value or potential side effects beyond the update itself. Since output schema exists, return value detail is less critical, but additional context on success/failure behavior would be beneficial.

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 description provides parameter descriptions in the docstring: avatar_id as UUID, name as internal name, display_name as display name. Since schema description coverage is 0%, this adds essential meaning beyond the bare schema titles. However, it does not cover any edge cases or format constraints.

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 'Update a custom avatar' and emphasizes partial updates with 'Only provide the fields you want to change.' This distinguishes it from create, get, delete, and list avatar tools among siblings.

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 implies partial update semantics ('Only provide the fields you want to change'), but does not explicitly state when to use this tool versus alternatives like create_avatar or delete_avatar, nor does it mention prerequisites or exclusion criteria.

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