channel_set_step_params

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

With no annotations provided, the description carries the full behavioral burden and does so reasonably: it discloses partial updates ('Only provided keys are written'), defaulting behavior ('pattern defaults to the current pattern'), and value ranges (velocity 0..127, pan 0..127 with 64=center). It does not cover error behavior or return values, but the mutation semantics are clear for a write tool.

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 description is compact and front-loaded: purpose first, then data format, then key behavioral notes. The '...'/'etc.' placeholders are imprecise but do not bloat the description, and every sentence earns its place.

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 3-parameter tool with no annotations, no output schema, and an open-ended steps object, the description should fully specify accepted keys, units, and every parameter. It handles steps and pattern well, but omits index and leaves the key set open-ended, so an agent could supply unsupported keys. It is usable but not fully complete.

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 inline format is essential; the description documents the structure of steps and clarifies the pattern default. However, it never explains the 'index' parameter at all, and 'pitch' is left as '...' so agents cannot know its range or format. This is partial but not full compensation for an empty schema.

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 uses a specific verb ('Write') and a concrete resource ('per-step graph-editor values'), then enumerates supported keys (velocity/pan/shift/pitch). It distinguishes itself from on/off grid-bit tools by saying 'adds groove and dynamics beyond on/off grid bits,' which differentiates it from sibling tools like channel_set_grid_bit or channel_set_step_sequence.

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 implies a clear use case: per-step expressive parameters rather than binary grid bits. However, it never explicitly names alternatives or states when not to use this tool. It does provide a useful usage default ('pattern defaults to the current pattern') but lacks explicit exclusions or alternative routing.

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