List blocked users

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

Annotations already indicate read-only and open-world behavior, so the bar is lower. The description adds meaningful context about scope ('the authenticated account') and the purpose of the returned ids, going beyond what annotations alone convey. It does not contradict 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?

A single, front-loaded sentence that states the action, scope, and output purpose without any filler. Every phrase earns its place.

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 zero parameters and an output schema already present, the description fully equips an agent to invoke the tool correctly. It also connects the result to the unblock workflow via the block ids, covering the practical downstream use.

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?

The tool has zero parameters, so the schema covers all parameter needs. The description does not need to provide parameter details; mentioning block ids as output is helpful but not a parameter-semantics requirement.

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?

Description clearly states the action 'List' and the specific resource: users the authenticated account has blocked from messaging it. It also explains the value of the returned block ids, which distinguishes this tool from generic list tools and from the block_user/unblock_user siblings.

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?

The description makes the use case clear: retrieve blocked users and obtain block ids needed to undo blocks. It does not explicitly name alternatives or state when not to use this tool, but the context is unambiguous for an agent choosing between this and messaging/blocking tools.

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