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

Annotations already flag destructive=true and idempotent=false, but the description adds substantial context beyond them: spend history is preserved, subsequent writes fail with agent_secret_mismatch, the agent_id remains claimed so no other workspace can inherit the ledger, and the owning workspace_key is required. This is exactly the kind of consequence detail an agent needs before a destructive call.

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?

Front-loaded with the core action and its key non-effect, then usage, then side effects, then return shape. Every sentence carries information; no filler.

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 purpose, trigger conditions, irreversible-ish consequences, auth requirement, and even names the return fields despite an output schema existing. Nothing an agent needs to call this destructive tool correctly 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 0% for both parameters, so the description must compensate. It states that workspace_key must be the key that owns agent_id, establishing the ownership/authorization relationship between the two parameters, though it does not describe agent_id's format beyond identity.

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 (invalidate/revoke), the exact resource (agent_id's agent_secret), and a delimiting scope clause ('WITHOUT deleting its spend history') that distinguishes it from sibling ledger_rotate_secret. An agent can tell this apart from rotation without opening either 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?

Gives two clear triggering conditions ('credential may have leaked', 'stop an agent writing') and implicitly routes to rotation via 'until you rotate a new secret in'. It does not explicitly name ledger_rotate_secret as the follow-up alternative, so it stops short of full when/when-not routing.

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