go_to_region

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

The description succinctly states the effect — moving the cursor — which is the core behavioral trait. Annotations already set destructiveHint to false, so no contradiction exists. However, it does not add context about edge cases (e.g., invalid region_index) or what the cursor movement implies for playback, though this is minor for such a simple operation.

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 a single clear sentence with no redundant words. It is well-structured and front-loaded, but the extreme brevity sacrifices needed parameter context — though that is more a completeness issue than a conciseness one.

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 only one parameter with zero schema description and no output schema, the description must compensate but fails to explain the region_index semantics. The tool is otherwise simple and non-destructive, yet the parameter gap makes it incomplete 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% and the description never mentions the region_index parameter. It only says 'a region start' without clarifying that the index refers to the region list, whether it is zero-based, or any constraints. The agent must guess the meaning of the sole required parameter, a critical gap.

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 exactly what the tool does — moves the edit cursor to a region start — using a clear verb and resource. It is distinguishable from the sibling go_to_marker, which targets markers, so there is no ambiguity about its function.

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 no guidance on when to use this tool versus alternatives like go_to_marker or other navigation commands. It does not mention context, preconditions, or exclusions, leaving the agent to infer the appropriate use case.

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