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

Goes well beyond the readOnly/idempotent/non-destructive annotations: it discloses that nothing is notified, existing requests are untouched, an approval-scope confirmation is required, and the call returns an exact preview plus a five-minute confirmation token. This is exactly the mutation-safety context an agent needs before a create flow.

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?

Three short sentences, front-loaded with the action and scope, then the non-effects, then the prerequisites and return nature. No filler and no repetition of the title.

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?

With no output schema, the description correctly explains what comes back (preview plus five-minute token) and what the tool will not do. For a single nested-object parameter it is nearly complete; only the condition-field semantics remain unaddressed.

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 0%, so the burden falls on the description, which adds meaning for two nested fields ('optional role chain', 'required decision notes'). However, priority, auto_escalate_after_hours, required_approver_role, and the condition field/operator vocabulary are left entirely to the schema enums, so compensation is only partial.

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 ('Prepare a rule requiring human approval') and scopes it to 'future matching invoices'. It implicitly separates itself from create_approval_rule by noting 'it does not apply the change', though it never names the sibling preview_approval_rule or create_approval_rule directly.

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 clear context: use it to stage a required-approval rule for future invoices, with the explicit caveat that it neither notifies nor alters existing requests. It implies the confirmation token is the follow-up step but never names which tool applies the change, leaving a small inference gap.

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