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

Annotations only say readOnlyHint=false. The description goes further and exposes the key behavioral nuance: this is a full overwrite, so any omitted webhook trigger is removed (creates/disables live webhook rows). That is exactly the kind of consequence an agent must know before invoking.

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?

Two sentences carry the definition: the first states action and semantic effect, the second states the call-style restriction. Zero filler and the most important information (replacement semantics) is front-loaded.

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 write-only setter with 2 fully documented parameters and no output schema, this description is complete enough. It covers what the tool does, how it behaves, and the one critical trap (omitted triggers are removed). It could mention return behavior or idempotency, but those are not needed for a normal agent invocation.

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 already has 100% description coverage for both parameters, including the 'complete list' and 'only one blank-slug default webhook' constraint. The description adds value by reinforcing that the list is the whole desired state, not a patch delta. This is useful but not drastically new after the strong schema.

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 a specific verb 'Replace' and clarifies the resource: the agent's trigger list. This clearly distinguishes it from siblings like set_schedule or set_governance_policies, and the parenthetical about live webhook rows puts the tool in a specific configuration niche.

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 instruction to 'Send the full desired list' and the warning that 'omitted triggers are removed' establishes a clear usage protocol: do not just update, replace. It doesn't explicitly mention when not to use the tool or name an alternative, but the replacement semantics give enough context for correct selection and invocation.

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