crosspad_snapshot

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

Annotations already establish readOnly/idempotent/non-destructive, and the description adds meaningful behavior: refs are ENC_GROUP indices invalidated by UI actions, next snapshot re-mints them, diff_from appends changed, unknown diff id falls back to full snapshot, and sim mode nulls ui. This goes well beyond the annotations.

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 dense but tightly organized: snapshot contents first, then the subtle ref invalidation warning, then the two optional modifiers. Every clause earns its place and important caveats are front-loaded before parameter details.

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 read-only snapshot tool with an output schema, the description is complete: it covers all parameters, edge cases (unknown diff_from, sim-specific ui null), device selection defaults, and behavioral invariants around refs. No meaningful gap remains for an agent to call it correctly.

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?

The schema covers 100% of parameters, and the description enriches each one: include sections map to 'fewer CDC round-trips', target=sim maps simulator stats and nulls ui, diff_from adds changed and handles unknown ids, and device omission is valid when only one CrossPad is connected.

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 opens with 'One-call state snapshot' and enumerates the exact sections returned (apps, ui, kit, leds, pads, mem, ble, console), making the tool's verb and resource unmistakable. It also distinguishes the hardware and simulator modes, so it is not confused with sibling build/flash/task tools.

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 gives strong usage context: device or sim selection, default behavior, optional include filtering, and diff_from semantics. It does not explicitly name sibling tools or state when not to use the snapshot, but the tool is clearly a read-only introspection utility and the guidance is otherwise concrete.

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