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

Annotations already declare destructiveness, idempotency, and non-read-only behavior, but the description adds important operational context beyond them: the deletion is permanent, the tool refuses while postcard templates still print the code, mailed postcards continue redirecting, and explicit user confirmation is required. No contradictions 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?

Four short sentences, each carrying distinct operational value: what it does, the blocking precondition, the side effect on already-mailed postcards, and the confirmation requirement. The core action is front-loaded with no redundant restatement.

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 destructive mutation with no output schema, the description supplies the missing behavioral and procedural context: permanence, refusal condition, required preceding action, and confirmation requirement. Combined with complete annotations and full schema coverage, an agent has everything needed to call it safely.

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%, and the schema already explains both parameters in detail, including that 'confirm' must only be true after explicit user approval. The description reinforces the confirmation requirement but does not add parameter format or syntax beyond what the schema provides, so the baseline of 3 is appropriate.

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 ('Permanently delete a QR code') and immediately distinguishes this operation from related QR-code workflows by naming the sibling tool used when templates still reference it. An agent can identify the action and its scope 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 says when the tool will be refused and names the alternative tool to use first ('spur_remove_postcard_qr_code'). It also gives a direct prerequisite instruction: 'Confirm with the user first.' This covers both when to use 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.