get-photo

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

With no annotations provided, the description carries the burden of behavioral disclosure. It transparently states the return format (data URI, 48x48) and the null behavior when no photo exists. It does not address error cases or side effects, but as a read-only getter, this is reasonably complete.

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 phrase that conveys the essential information without filler. It is front-loaded with the core purpose and output characteristics, adhering to the principle that every word earns its place.

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 one-parameter getter with no output schema, the description covers the key aspects: return type, size, and null case. It could benefit from mentioning the parameter explicitly, but given the tool's low complexity, the description is nearly complete.

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 schema has zero description coverage for the single parameter 'userId'. The description only says 'for a user', which hints at the parameter's purpose but does not explain its format, constraints, or relationship to other user identifiers. The description adds minimal value beyond the schema's property name.

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 specifies the tool's function: retrieving a user's photo as a data URI with a fixed size (48x48), and notes the possibility of null. This is a specific resource (photo) with a clear output format, distinguishing it from sibling tools like visualize-identity or get-manager.

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?

No guidance is provided on when to use this tool versus alternatives. The description implies a simple photo retrieval, but there is no explicit context, prerequisite, or comparison with sibling tools such as visualize-identity, which could be a potential alternative for user identity information.

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