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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so safety is covered. The description adds one genuinely new behavioral fact - that an idempotency key is generated on a best-effort basis - but says nothing about normalization rules, determinism of the key, or failure behavior (the schema covers the ok:false case).

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?

One dense sentence with zero filler; the core action and the extra idempotency-key behavior are both front-loaded. Nothing could be removed without losing information.

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?

With an output schema present and annotations covering safety, the description does not need to explain returns. However, for a tool whose name promises normalization, it never says what normalization entails or which fields are canonicalized, leaving a meaningful gap in an otherwise simple definition.

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 description coverage is 100% and the single `payload` parameter is documented thoroughly in the schema (accepted types, required envelope fields, ok:false fallback). The description adds no parameter-level detail beyond that, so the baseline of 3 applies.

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 pair (validate/normalize) on a specific resource (GrowSurf webhook payload) plus a concrete secondary output (idempotency key). It is clearly distinct from the webhook CRUD siblings (list/create/update/delete/test_campaign_webhook), though it never names or contrasts with any sibling explicitly.

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?

Usage is only implied: the mention of 'dedupe' hints that this is for inbound webhook handling, but there is no explicit when-to-use, when-not-to-use, or alternative tool named. An agent must infer the scenario.

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