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

Annotations already declare destructiveHint=true, readOnlyHint=false, idempotentHint=true, but the description goes further: it spells out the real-world consequence ("live calls stop transferring to it") and emphasizes "REAL ACTION, not a preview." It also imposes a confirmation protocol, which is exactly the behavioral context 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?

Four short sentences, front-loaded with the purpose, then the safer alternative, then the risk, then the required confirmation step. Nothing is redundant and the ordering matches decision order.

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 two-parameter tool with no output schema, the description covers scope, risk, alternative, and the confirmation protocol. There is no meaningful gap an agent would need filled before invoking it.

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 100%, so both agentId and transferShortId are already documented (including the 4-character format and source endpoint). The description only restates transferShortId as the selector and adds no format or sourcing detail beyond the schema. Baseline 3 applies.

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 remove one transfer number"), pins the scope to a single record, and names the key identifier (transferShortId). It is unmistakable against siblings like transfer_numbers_list, transfer_numbers_update, and transfer_numbers_reorder.

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 routes the agent to the softer alternative: "Prefer transfer_numbers_update with isActive=false to pause it." This gives both a when-to-use and a when-not-to-use with the named substitute, plus the pre-call confirmation requirement.

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