windows_snapshot

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds genuine value by disclosing the return contents (stable runtime refs, control names/types, supported patterns, bounds), which no output schema exists to convey.

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?

Three compact sentences, front-loaded with the mechanism and purpose, then return values, then the routing hint. Nothing is padded, but the routing sentence is a fragment that could be folded in.

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?

No output schema, so listing return contents is the right move. Remaining gaps: no guidance on pid vs title selection strategy, and no explanation of the undocumented maxElements/includeOffscreen parameters. Adequate for invocation basics, incomplete on tuning.

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 only 50%: pid and title are documented (including 'alternative to pid'), but maxElements and includeOffscreen have no schema description and the tool description says nothing about parameters at all. The description does not compensate for the coverage gap.

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+resource ('Semantic Windows UI Automation snapshot of a native app window') and clarifies the underlying mechanism (UI Automation), which separates it from the pixel-based windows_screenshot. It stops short of naming the sibling it replaces explicitly, only gesturing at 'coordinate clicking'.

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?

'Prefer this over coordinate clicking' gives a directional preference, but no when-not condition and no named alternative tool (windows_screenshot or windows_action are never mentioned). Usage is implied rather than spelled out.

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