get_composite_pixel

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

With no annotations, the description carries the full burden of behavioral disclosure, but it only says the tool reads and returns one RGBA pixel. It does not explain coordinate semantics, frame_index handling, visibility rules, or edge-case behavior such as out-of-bounds coordinates.

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 efficient sentence with the operation and target front-loaded and no wasted words. It is concise and scannable, though the brevity contributes to the missing parameter and behavior detail penalized elsewhere.

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 no output schema, no annotations, and 0% schema description coverage, the description is not complete enough to support confident invocation. It omits coordinate system, frame selection, edge cases, and a precise return-format statement beyond 'RGBA pixel.'

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 names none of the four parameters. The agent receives no explanation of what filename means, how x and y coordinates are interpreted, or how frame_index affects the result beyond the bare schema types and defaults.

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?

States a clear verb ('Read') and a precise resource ('one RGBA pixel from the visible flattened composite'), which helps distinguish it from layer-based or area-based pixel tools like get_pixel_color. However, it does not explicitly contrast itself with siblings such as get_composite_rect, so full differentiation is left implicit.

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?

No guidance is given about when to use this tool versus alternatives like get_pixel_color, get_pixels_rect, or get_composite_rect. The phrase 'visible flattened composite' implies a use context, but there are no explicit when-to-use or when-not-to-use statements.

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