Edit region

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

With no annotations, the description carries the full burden and does meaningful work: it discloses that the range is clamped to the source audio and, importantly, that clips have no length of their own so a retrim affects every clip using the region – a non-obvious side effect. It stops short of covering permissions or what the response 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?

Two sentences, zero waste, and the primary action plus its most important consequence (retrim affects every clip) are front-loaded.

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 mutation tool with no annotations and no output schema, the description covers the key behavioral risk (shared-clip side effect) and the clamping constraint. It could add rename-collision behavior and required-permission context, but the essentials are present.

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 100%, so the schema already documents all 8 parameters (including unit, start/end/length exclusivity, and rename collision rules). The description only adds the source-relative/clamping framing, which is marginal beyond the schema; baseline 3 applies.

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 specific verbs (renames, retrims) and the resource (a region's source-relative range). It clearly contrasts with sibling create_region/cleanup_regions by implying an edit of an existing region, though it never names a sibling 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?

Usage is implied by 'renames a region and/or retrims' – the agent can infer this edits an existing region rather than creating one. However, there is no explicit when-to-use vs. alternatives guidance (e.g., versus create_region or cleanup_regions) and no stated prerequisites.

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