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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the safety profile is known; the description adds nothing beyond it. For a destructive mutation it never says whether exercise_ids replaces or appends to the existing list, whether omitted fields are preserved, or what permissions are required — the exact behavior an agent most needs here.

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 short sentences, verb and scope first, trigger condition second. No filler or repetition of the schema.

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?

An output schema exists so return values need no explanation, but for a destructive 7-parameter mutation with 0% schema coverage the description is too thin. Replacement vs. merge semantics and the required group_id handling are left entirely to inference.

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 and it only covers four of seven fields (name, exercises, rounds, rest time). It omits the required group_id, team_id, and the group_type enum, and critically never clarifies whether exercise_ids is a full replacement or a delta.

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?

States a specific verb+resource ('Updates an exercise group') and enumerates the mutable fields, so the agent can distinguish it from create_exercise_group. It does not explicitly name or exclude a sibling, which keeps it short of a 5.

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?

'Use when the user wants to change name, exercises, rounds, or rest time' gives a concrete trigger condition. It offers no exclusions or alternatives (e.g., when to use create_exercise_group instead, or what to do for group_type changes), so it stops at clear-context-no-exclusions.

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