histogram

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the 'Read-only' statement adds little. The description does add useful context: histograms are per-channel and default to 256 bins. However, it does not disclose return format, behavior when bins is omitted, or how channels are represented.

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 very short and front-loaded with the core purpose. The final 'Read-only' is somewhat redundant with the readOnlyHint annotation, but it does not add meaningful bloat. Overall it is efficient and scannable.

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?

For a simple read-only tool with two parameters, the description gives enough to guess the basic call, but it lacks details about the return structure, channel ordering, or how the bins parameter is applied. With no output schema, a bit more context about the returned histogram data would improve completeness.

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 adds meaning for bins by noting the default of 256, and 'for a view' gives some context for the id parameter. However, it does not explicitly define id as a view identifier or explain how bins affects the output beyond bin count.

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 that the tool produces per-channel histogram counts for a view and mentions the default of 256 bins. It lacks an explicit verb like 'compute' or 'return,' and it does not explicitly distinguish itself from close siblings such as image_statistics, but the histogram concept is specific enough to be identifiable.

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 provides no guidance on when to use this tool versus alternatives like image_statistics or scan_frames. It only says 'for a view' and 'Read-only,' which implies a safe inspection use case but does not state exclusions or mention a better-suited sibling.

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