update_device_fingerprint_preview

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

Description explicitly states read-only, no DB write, no last_seen or updated_at mutation, aligning with annotations. It adds value beyond annotations by detailing merge rules (top-level overwrite, capabilities one-level overwrite) and idempotency implied.

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?

Description is a single paragraph but packs essential information: purpose, merge rules, read-only nature, and phase reference. Slightly front-loaded but effective.

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 simplicity of the tool (two params, clear behavior), the description covers merge behavior and read-only guarantee. No output schema but description hints at return type. Annotations complement well.

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 provides full coverage with descriptions for both parameters. Description adds minimal extra semantics (e.g., shape of fingerprint referencing update_device_fingerprint). Baseline adjusted for high schema coverage.

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 name and description clearly state this is a preview of updating device fingerprint without persistence. It distinguishes itself from the sibling update_device_fingerprint by explicitly mentioning 'Preview' and 'without persisting', and specifies merge rules.

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 explains when to use (to preview merge result before committing) and that it is read-only. It does not explicitly contrast with other preview tools, but the context is clear enough for an AI agent to decide.

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