Capture N GL commands

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

Annotations provide readOnlyHint=false, destructiveHint=false, so the tool performs a write operation but is not destructive. The description adds 'startCapture for a fixed command count', which aligns. However, it does not disclose side effects like clearing previous captures or performance impacts, which would add value given the minimal annotation 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 sentence with no redundant words, front-loading the core purpose. It is appropriately concise, though it sacrifices parameter detail for brevity.

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 9 parameters, no output schema, and minimal annotations, the description is incomplete. It omits parameter explanations, return behavior, error conditions, and usage context, leaving significant gaps for an AI agent.

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 compensate. It only implies the 'commandCount' parameter via 'fixed command count', but does not explain the other 8 parameters (label, canvasId, timeoutMs, etc.). The description adds no meaning beyond the schema, failing to help an agent understand parameter usage.

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 'Capture N GL commands' and 'capture an arbitrary stage without waiting for a full frame boundary', which distinguishes it from siblings like webgl_capture_frame (captures a full frame) and webgl_capture_sequence (captures a sequence of frames). It specifies the verb (capture) and resource (GL commands).

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 explicitly says 'capture an arbitrary stage without waiting for a full frame boundary', implying when to use this tool (when you need a fixed command count instead of a full frame). It does not explicitly state when not to use or name alternatives, but the sibling context and description provide sufficient guidance.

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