update_output_guardrail_workspace_exclusions

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

Annotations already flag destructiveHint and idempotentHint, but the description adds genuine context beyond them: default merge vs override_existing replacement semantics, immediate enforcement, the idempotency granularity ('repeating the same states is safe'), the required organisation_exclusions.update scope, Enterprise gating, and the concrete 403 failure mode.

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?

Five tight sentences, front-loaded with the action and its merge semantics, followed by ordering advice, idempotency reassurance, and auth/gating constraints. No filler or restated field names.

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?

Covers the mutation semantics, prerequisites (list tool, scope), and the Enterprise-gating error case; an output schema exists so return values need no explanation. Nothing an agent needs to invoke this safely is missing.

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 coverage is 100%, so the baseline is 3; the description earns an extra point by explaining merge-vs-replace behavior of override_existing and clarifying that unmentioned workspaces are preserved, which the schema's one-line field description does not spell out.

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 and resource ('Set workspace exclusions from organisation-wide output guardrails') and implicitly distinguishes itself from the list_* and update_input_guardrail_* siblings by naming the output-guardrail scope. An agent can identify what this mutates without opening the schema.

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?

Explicitly instructs the agent to call the matching list tool first because enforcement changes immediately, which is real ordering guidance. It stops short of naming that sibling explicitly or stating when to prefer this over update_input_guardrail_workspace_exclusions, so 4 rather than 5.

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