wpf_diff

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

No annotations are provided, so the description carries full burden. It clearly discloses the output: 'Returns a summary (counts) plus, for each element that changed, the exact properties that changed (from → to), keyed by stable element handle; plus elements added or removed between the two snapshots.' No contradictions.

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 concise, front-loaded with the purpose, and efficiently describes the output structure without superfluous text. Every sentence earns its place.

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?

The description explains the return value in detail (compensating for no output schema) but lacks parameter semantics. For a 2-parameter tool, this is a notable gap, making it somewhat incomplete for an agent to use correctly without additional context.

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 0%, so the description must add meaning. It mentions 'before' and 'after' as snapshot names but does not explain their format (e.g., file paths, data content). The description only implies they are snapshots captured with wpf_snapshot, leaving ambiguity for the agent.

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 uses specific verbs and resources: 'Diff two snapshots captured with wpf_snapshot, to measure the effect of a change.' It clearly distinguishes from sibling tools like wpf_snapshot (which captures) and others.

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 to verify a planned UI tweak did what you expected' and provides concrete examples. It implies a workflow with wpf_snapshot but does not explicitly mention when not to use it or alternatives.

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