Update GTM Trigger

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

Annotations already declare readOnlyHint=false, destructiveHint=true, idempotentHint=true, so the description does not need to repeat safety traits. It adds valuable behavioral context beyond annotations: 'Only the provided fields are changed' clarifies partial update semantics, and 'provided filter arrays replace the existing ones wholesale' explains replacement behavior. This is useful and not redundant with 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?

Two clear sentences conveying essential behavior without fluff. The first sentence states purpose, the second adds critical update semantics. Efficient and front-loaded. Could be slightly more structured (e.g., bullet points) but it is appropriately concise for its content.

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 complex update tool with nested filter structures and no output schema, the description covers the key update semantics (partial vs. wholesale replacement). It does not describe the result or error handling, but with no output schema, that expectation is lower. The description is adequate for an agent to understand what will happen without over-specifying.

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 each parameter is documented (e.g., filter descriptions mention 'replaces existing'). The description adds a global note about updating only provided fields, which reinforces param semantics but does not explain individual parameters beyond what schema already provides. Baseline of 3 is appropriate given full 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 description clearly states the action ('Update an existing trigger in a workspace') with a specific verb and resource. It distinguishes from create/delete by the word 'existing', but does not explicitly contrast with get or list operations. Clear enough for basic selection among siblings.

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 context is implied: this is for updating an existing trigger, not creating or deleting. However, no explicit when-to-use or when-not-to-use guidance, nor mention of alternatives. The description does not state prerequisites (e.g., must have the trigger ID) but that is evident from required parameters. Minimal guidance beyond the obvious.

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