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

With no annotations, the description carries the full burden. It usefully discloses the auth requirements (platform staff, account session, manage permission), which is real context for a mutation. However, it says nothing about idempotency, what happens if the number is not on the list, or reversibility of the removal.

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 with the access restrictions front-loaded before the action. No filler or repetition. Slightly telegraphic ('Requires manage') but every clause carries information.

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 one-parameter mutation with no annotations and no output schema, the description covers authorization and the action but omits failure modes and whether the removal is idempotent. Adequate to invoke, incomplete for predicting behavior.

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 schema only enforces an E.164-like pattern without explaining it. The description refers to 'a number' but does not add format guidance or constraints beyond the parameter name, leaving the schema's regex as the only signal.

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: 'Remove a number from the platform do-not-call list.' It is clearly distinct from the sibling platform_blocklist_add and platform_blocklist_list by the verb alone. No explicit sibling naming, but the action is unambiguous.

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 the gating conditions up front: platform staff only, account session, requires manage permission. That tells an agent both when it may call this and when it should not. It stops short of naming the alternative tool or describing behavior when the number is absent from the list.

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