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

With no annotations provided, the description carries the full behavioral burden, and it excels: it discloses idempotency ('already-absent fields report removed: false without rewriting the vault'), keying semantics ('what is vaulted, not what the current template declares'), and destructiveness ('as destructive as a write'). The proof requirements and rejection of patron proofs are also clearly stated.

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?

The first sentence delivers the core action, and each subsequent sentence adds a distinct, non-redundant fact: scope, use case, idempotency, privilege, and destructiveness. The length is justified by the tool's security- and semantics-rich nature; nothing feels padded.

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 sensitive mutation tool with no annotations, the description covers invocation intent, preconditions, security requirements, edge behavior, and side effects. The presence of an output schema means return-format explanation is unnecessary. An agent has everything needed to select and invoke this tool correctly.

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?

Although the input schema covers basics, the description adds deep meaning: 'field' is explicitly templated-or-not and vaulted-or-templated, while 'dpop_token' is enriched with concrete proof forms (nsec-signed kind-27235 or cached dpop_token phrase). This goes well beyond the schema's one-line descriptions.

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 opens with a precise verb-object pair — 'Remove a single operator secret field' — and immediately clarifies it deletes one key from the encrypted credential blob. It explicitly distinguishes itself from the sibling 'forget_credentials' (whole-row wipe) and from patron-credential tools by emphasizing operator scope. This is a model example of sibling differentiation.

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?

It names the exact scenario — retiring leftovers after an SDK cutover, like a Prefect key after Modal or an untemplated orphan — and contrasts with 'forget_credentials' for full re-delivery. It also declares eligibility constraints: operator-only, requires specific proof, and patron proofs are rejected. The agent knows when to call it and when not to.

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