start_obs_recording

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

The description adds context beyond the readOnlyHint=false annotation by disclosing that it selects and verifies the OBS source before starting recording. However, it does not mention potential side effects like launching OBS (as hinted by the launch_if_needed parameter) or failure modes when the source is not configured. With annotations providing the mutation hint, the description gives some added context but not rich detail.

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 concise sentence, front-loaded with the action verb and resource. Every word contributes meaning, and it is not padded with redundant information.

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?

The tool has side effects, depends on OBS state, and has no output schema. The description does not explain return values, prerequisites (e.g., OBS must be running), or how it integrates with sibling tools like open_obs or get_obs_status. It is too minimal for a mutation tool with complex behavior.

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 only 25% (only avd_name has a description). The tool description helps clarify the 'target' parameter by mentioning emulator or physical device, but it provides no additional meaning for 'timeout_ms' or 'launch_if_needed'. With low schema coverage, the description carries a heavy burden and fails to compensate for the missing parameter documentation.

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 clearly states the tool's function: 'Select and verify the configured OBS source for an emulator or physical device, then start recording.' It specifies the verb (start recording), the resource (OBS source), and the target scope (emulator or physical device), distinguishing it from sibling tools like stop_obs_recording and get_obs_status.

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 usage when you want to record screen activity for a specific target, but it does not explicitly state when to use this tool versus alternatives, nor does it mention prerequisites like OBS being open or checking status. There is no exclusion or alternative guidance.

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