analyze_performance

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It transparently explains dependencies, fallback behavior for untimed passes ('fill workload when untimed'), and what analytical outputs to expect. It could go further by stating that the operation is read-only or how it handles invalid/old captures, but the disclosure is otherwise strong.

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 dense but every clause earns its place: it states the goal, lists the verdict and ranked analyses, notes the conditional requirements in parentheses, and closes with an explicit recommended pairing. Important conditions are front-loaded, and there is no filler or repetition.

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?

Despite having no output schema, the description enumerates what the tool returns: frame budget, bound verdict, ranked render passes with size/format/MSAA/blend/shader annotations, bottleneck classification, heuristic issues, and ranked suggestions. It also covers the necessary capture conditions. For a single-optional-parameter analysis tool, nothing essential is missing.

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?

The only parameter, captureId, is already fully described in the schema as 'Capture id (default: most recent)', and schema coverage is 100%. The description adds useful capture-quality context via the capture_frames pairing but does not add parameter-specific semantics beyond the 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 opens with a specific verb-resource pair ('Diagnose a capture's performance') and a distinct deliverable ('concrete improvement suggestions'). It then enumerates unique outputs—frame budget, CPU/GPU/vsync verdict, ranked passes with bottleneck annotations, heuristics—that clearly set it apart from siblings like get_frame_stats or get_capture_summary.

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 gives explicit prerequisites: a live capture for CPU/refresh context and profilePasses:true for GPU time, plus a recommended capture_frames invocation. It does not explicitly discuss when not to use the tool or mention alternative tools, so it stops just short of full routing guidance.

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