piano_roll_goto

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

With no annotations provided, the description carries the full behavioral burden. It discloses the internal call sequence ('channels.select → patterns.select → ui.openPianoRoll') and the idempotent behavior ('Does nothing if already on the target pattern'). It does not mention error behavior or return values, but the core side effects are transparent.

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 tight and well-ordered: purpose first, routing guidance second, implementation sequence third, idempotence fourth, and parameter details last. Every sentence adds necessary information with no filler.

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 two-parameter navigation command with no output schema and no annotations, the description covers what the tool does, how it relates to siblings, its operational steps, and parameter semantics. It could be slightly more complete by addressing invalid index handling or what 'target pattern' means relative to the channel, but it is largely sufficient for correct invocation.

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 fully compensate. It does: 'channel: Channel rack index (0-based)' and 'pattern: Pattern index (1-based, as returned by patterns.list)' add indexing conventions and provenance for both parameters, going well beyond the bare 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 states a specific verb and resource: 'Navigate the piano roll viewport to a specific channel × pattern.' It clearly differentiates itself from pattern_select and channel_select by naming them and declaring that this tool should be used instead, making its compound purpose unambiguous.

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 provides explicit routing guidance: 'Always use this instead of pattern_select / channel_select directly.' It also outlines the exact operation sequence. However, it does not describe when a caller might prefer the alternative tools (e.g., if only selection is needed without opening the piano roll).

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