pix_get_api_objects

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds valuable behavioral context beyond the annotations: results are per-thread and sparse, represented as spans, and act as an object-id-to-name mapping lane. It does not mention pagination or timeout behavior, but the annotations lower the burden and the added context is meaningful.

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 front-loaded with a crisp one-sentence summary, then adds purposeful detail about what the data means and how to discover populated threads. Every sentence earns its place; there is no fluff or repetition of schema/annotation 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?

Given the output schema exists, the description need not explain return values. It covers what the tool returns, why it matters, how it relates to object ids, and how to find a thread with data before querying. The main gap is parameter semantics, but that is already captured under parameter_semantics; for agent selection and safe invocation, the context is largely sufficient.

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 for parameter meaning. It implies thread_id via 'one thread' and 'per thread', and start_time/end_time via 'as spans', but it does not explain capture_id, limit, cursor_position, or timeout_seconds. With seven parameters and no schema descriptions, more parameter-level guidance is needed for correct invocation.

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 a specific resource and behavior: named D3D12 API work on one thread, as spans, and identifies this as PIX's API object lane. It clearly distinguishes itself from timing/event tools by explaining it maps object ids to names and shows compiles/resource creation on threads, which is unique among the sibling tools.

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 practical guidance: this tool is per-thread and sparse, and pix_list_timing_threads reports api_object_events on every row so the agent knows how to find a thread that has data before querying. It does not enumerate when-not-to-use cases against other siblings, but the primary discovery alternative is named and the usage context is clear.

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