Set own profile photo

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

The description does not disclose behavioral traits beyond the annotations. The openWorldHint and idempotentHint annotations already indicate external side effects and repeatability. The description adds no context about permissions, whether the old photo is replaced, side effects, or return behavior. For a mutation tool, this is a significant gap.

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 concise sentence that conveys the core purpose and input type without redundancy. Every word earns its place, making it highly efficient.

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 tool with 2 parameters and no output schema, the description is incomplete. It omits the role of 'accountId', provides no guidance on expected outcomes (e.g., new photo URL), and lacks behavioral details like authentication or replacement semantics. The description covers only the most basic purpose and one parameter's format.

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%, so the description must compensate. It clarifies that 'path' can be a local path or URL, which adds some meaning. However, the 'accountId' parameter is not explained at all, leaving ambiguity about its purpose. With only two parameters and one unexplained, the description does not adequately 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 clearly states the tool's function: 'Upload a new profile photo from a local path or URL.' It specifies the verb (upload), the resource (profile photo), and the input source (local path or URL), distinguishing it from siblings like download_profile_photo and edit_photo.

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 the tool is used for setting one's own profile photo and mentions accepted input formats (local path or URL). However, it does not explicitly state when to use this tool compared to alternatives like update_profile or edit_photo, nor does it provide exclusions or prior conditions.

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