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

Annotations already declare this a non-destructive, closed-world write, so the safety profile is covered. Beyond that the description adds nothing behavioral: the only extra statement ("Requires at least 2 exercise IDs") merely restates the schema's minItems/required constraints, and there is no mention of permissions, side effects on existing workouts, or whether the created group is later updatable.

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?

Three short sentences, front-loaded with the verb and resource, with no filler. The final sentence is partly redundant with the schema's minItems constraint, which keeps it from being maximally tight.

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 6-parameter mutation with zero schema documentation and no parameter guidance in the prose, the description is thin. An output schema exists so return values need not be explained, but an agent still lacks enough context to fill rounds, group_type, team_id, or rest_seconds correctly.

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% across 6 parameters, so the description must carry the load and it does not. It only implies that exercise_ids holds exercise identifiers; name, rounds, team_id, group_type, and rest_seconds get no explanation of format, defaults, or effect on the created group.

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 and resource ("Creates an exercise group") and clarifies the two variants it can produce (circuit or sets). It does not explicitly distinguish itself from the neighboring create_exercise_instance or update_exercise_group, so it falls 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 group exercises for circuits or micro-workouts" gives a clear triggering context, which is more than most definitions offer. However, it names no alternatives or exclusions — nothing says when to use update_exercise_group instead, or that the referenced exercises must already exist.

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