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

Annotations already declare the tool as read-only and idempotent. The description adds meaningful behavioral context: identity comes from the token rather than a caller-supplied user id, and the response is a subset ('slice') with configurable domains. No contradiction with annotations.

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?

Two concise sentences, each serving a distinct purpose: stating the function, default behavior, customization, and authentication. Front-loaded with the core action and free of 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?

The description adequately covers the essential aspects for a read-only tool with an output schema: purpose, default domains, customization via `domains`, and identity handling. Since an output schema exists, it does not need to describe return values or structure.

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 thoroughly explains the `domains` parameter, including accepted values and defaults, adding value beyond the schema. However, `workout_limit` is not mentioned at all, and the schema only provides a default with no purpose, leaving its meaning (likely limiting workout entries) implicit.

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 returns a slice of the signed-in user's training picture, explicitly listing default domains (workouts, nutrition) and optional domains (checkin, notes, profile). This distinguishes it from sibling getters that focus on individual domains, such as get_workouts or get_nutrition_daily.

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 usage for fetching a combined training context with configurable domains, and notes the authentication requirement (identity from token). However, it does not explicitly state when to prefer this over alternative single-domain tools, leaving the comparison implicit.

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