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

Annotations only declare readOnlyHint and openWorldHint, so the description carries the interpretive burden and meets it. It discloses subtle behaviors: hard_sets meaning (RIR≤3), the warning to never quote volume ('never volume'), the precedence rule for flags.plateau vs state.plateau_status, and role labels on top_exercises rows. No contradiction with the read-only annotation.

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 purpose is front-loaded in the first sentence, and every subsequent clause carries disambiguation value. However, the middle section reads as a dense payload unpacking that could have been tightened into an organized list, which slightly reduces scannability for an agent.

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?

With a full output schema present and read-only annotations covering the safety profile, the description supplies everything needed to select and invoke the tool correctly: field semantics, interpretation warnings, the alternative tool, and the intended use case. Nothing needed for correct usage is missing.

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 coverage is 100% (group and weeks both documented), so the baseline of 3 applies. The description adds little parameter-level detail beyond the schema, though 'Get weekly progress series' implicitly ties group to muscle-group selection and weeks to the series length.

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?

Opens with a specific verb and resource: 'Get weekly progress series for a muscle group.' It also disambiguates against siblings by stating that interpreted assessments belong to get_muscle_state and that this tool returns raw time-series data, which differentiates it from get_exercise_progress and get_strength_climb.

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 gives an explicit exclusion and alternative: 'For TIE's interpreted assessment (fatigue, plateau, effective volume), use get_muscle_state instead.' It closes by naming the intended use case ('raw time-series data useful for charting and external analysis'), leaving no ambiguity about when to choose this tool.

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