snapdiff_verify_ui_change

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

With no annotations provided, the description carries the full burden. It discloses key behaviors: requires a project and page baseline, explains the verdict values (pass, expected_change_detected, etc.), and instructs the agent to surface review_url while not sharing raw image URLs. It also describes how intent_regions affect verdict accuracy. While not exhaustive (e.g., missing error handling or rate limits), it provides substantial context.

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 the core action and usage guideline, then provides return value info, then parameter details. It is somewhat lengthy but each sentence adds value. Minor redundancy could be trimmed, but overall it is well-organized and easy to scan.

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 complexity (10 parameters, no annotations, no output schema), the description covers the return values and gives guidance on when to use optional parameters. It assumes baseline existence, which is reasonable given sibling tools. Some missing details (e.g., how to set up a baseline) are outside the scope of this tool's description, so completeness is good.

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 coverage is 100%, so baseline is 3, but the description adds significant value. For 'intent', it explains why it's required ('without it, the verdict cannot distinguish intended changes from regressions'). For 'intent_regions', it details the trade-off between selector and bbox, including how selector is resolved server-side. For 'match_tolerance_percent', it explains the default and when to adjust. This goes well beyond the schema.

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 starts with 'Verify a UI change you just made matches what you intended.' This clearly states the action and resource. It also explains when to use it: 'Use this whenever you modify a route, page, or component and need to confirm the visual result.' The purpose is specific and distinct from sibling tools like snapdiff_capture_baseline or snapdiff_check_build.

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 explicitly states when to use the tool: 'Use this whenever you modify a route, page, or component and need to confirm the visual result.' It does not explicitly mention when not to use it or provide direct alternatives, but the context is clear enough for an agent to understand the primary usage scenario.

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