pix_list_controllers

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

Annotations already establish read-only, idempotent, non-destructive behavior, so the description does not need to repeat that. The added latency_instrumented explanation provides some context about an output field, but it is confusingly worded ('which is the difference... when the title read them') and does not clarify pagination, ordering, or other behavioral details. It adds partial value but no contradiction with annotations.

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 short and the core idea is placed first, which is good. However, the first sentence is grammatically incomplete and the second is a run-on with unclear referents for 'which' and 'the title.' It is compact but not cleanly structured.

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?

An output schema and read-only annotations reduce the burden, but the description still leaves the operation implicit, provides no sibling differentiation, and leaves all parameter semantics undocumented. An agent could guess a basic capture_id call, but reliable use of limit, cursor_position, and timeout_seconds is not supported by this definition.

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 explains none of the four parameters: limit, capture_id, cursor_position, or timeout_seconds. The only weak connection is that 'capture' in the description implies capture_id, but limit, pagination cursor, and timeout behavior are completely undocumented. With zero schema descriptions and no compensatory explanation, this is a significant 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 identifies the resource ('input controllers the capture saw') and implies a listing operation, so an agent can roughly infer what the tool returns. However, it is a sentence fragment rather than an explicit 'Lists...' statement, and it does not distinguish this tool from siblings like pix_get_controller_input. Overall purpose is clear in substance but not precisely or independently stated.

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?

There is no guidance about when to use pix_list_controllers versus alternatives, no mention of prerequisites, and no mention of when not to use it. The only implied context is that a capture is involved, which is insufficient for an agent choosing among many similar capture-related tools.

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