playback

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

With no annotations, the description adequately describes each action's effect (play starts editor pattern, pause stops without resetting clock, stop ends playback). Lacks detail on state resets or session requirements.

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?

Compact and well-structured: purpose first, then actions, example, and cross-references. Every sentence adds value.

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?

Given simple schema (2 params, enum) and no output schema, the description fully covers usage, behavior, and alternatives. No gaps identified.

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%, but description adds meaning to action enum (play/pause/stop behaviors) and clarifies session_id optionality, exceeding baseline 3.

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?

Clearly states 'Control transport on the current session' and lists specific actions (play, pause, stop), distinguishing itself from siblings like edit_pattern and set_tempo.

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?

Provides explicit actions and example, and directs when to use alternative tools (edit_pattern, set_tempo). Could further clarify prerequisites like session readiness.

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