set_time_signature

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

With no annotations, the description carries the full burden. It discloses the behavioral difference between setting at bar 0 and adding a change at a given bar, which is genuinely useful, but it does not state whether an existing signature at that bar is overwritten, whether the change can be reverted, or what the call returns.

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 core behavior and the worked example come first and are compact, with no filler. The bilingual duplication roughly doubles the length, but each sentence still conveys the same concrete information rather than padding.

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 simple three-parameter mutator with no output schema, the description covers mode selection and parameter meaning adequately. It falls short of complete because overwrite semantics and any return/undo information are unstated, which matters for a state-changing call with no annotations.

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 0% and property titles ('Beat Unit', 'Beat Per Bar') are ambiguous, so the example mapping 3/4 to 3, 4 meaningfully disambiguates which parameter is the numerator and which is the denominator note value. It also explains the role of bar. Minor gap: it does not spell out that beat_unit is a note value such as 4 = quarter note.

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 names a specific verb and resource ('Set the time signature') and clarifies the two modes: bar 0 for the initial signature, or a bar number to insert a change. That is clearly distinct from siblings like set_tempo or set_key, though no sibling is named explicitly.

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?

It does explain the condition that selects each behavior: omit or use bar 0 to set the signature, specify a bar to add a change there. What is missing is guidance on prerequisites, ordering relative to other setup calls, or what happens if a signature already exists at that bar.

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