get_changes_since

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

No annotations are provided, so the description carries the full burden. It adds the useful behavioral trait of returning only modified regions and pixel deltas, which clarifies output nature. However, it omits details like what constitutes a 'modified region' (format, granularity) and any performance or permission considerations.

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?

A single, front-loaded sentence that efficiently conveys purpose and benefit without any fluff. Every clause earns its place by clarifying the differential nature and the avoidance of full reads.

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 simple one-parameter tool and lack of output schema, the description is largely complete. It explains what is returned (modified regions and pixel deltas) and the efficiency benefit. It could be improved by specifying the return structure or revision format, but for a diff tool this is adequate.

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 100%, and the parameter 'sinceRevision' is documented in the schema as 'Base revision to diff against.' The description adds no additional meaning beyond what the schema provides, so baseline 3 applies.

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 specific verb and resource: returns modified regions and pixel deltas since a revision. The phrase 'Differential inspection' and mention of avoiding full canvas re-read clearly distinguishes this from get_canvas and get_pixel_grid.

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?

Implies usage context with 'avoiding re-reading the entire canvas,' suggesting it's for efficient delta tracking. However, it does not explicitly state when to choose this over get_canvas or get_pixel_grid, nor does it mention any prerequisites.

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