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

Annotations already declare this as read-only, open-world, idempotent, and non-destructive, so the baseline is high. The description adds the key behavioral constraint of 'up to 20' results and 'no account required', which informs the agent about rate or scope limits. It doesn't contradict annotations, and these additions are meaningful beyond the annotation flags.

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?

The description is a single, front-loaded sentence that states the action, scope, and limit without any fluff. Every word is purposeful, and the 'no account' note is efficiently included. This is a model of clean, minimal writing.

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?

Given the zero-parameter simplicity, the high annotation coverage, and no output schema, the description is largely complete. It tells the agent exactly what to expect (up to 20 items) and any prerequisites (none). The only minor gap is not specifying whether the results are sorted or in any particular order, but that is not critical for a simple list tool.

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?

Since there are no parameters, the description doesn't need to explain any. The schema is empty with 100% coverage, so the description's mention of '20' sets the expected limit. This is sufficient; a higher score would be unjustified because there is no parameter behavior to elaborate on.

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?

The description clearly states the tool reads up to 20 recent public exchanges, specifying both the action (read) and the resource (public exchanges). It differentiates from siblings like search by highlighting recency and public scope, and the zero-parameter schema makes the purpose 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?

The description implicitly communicates when to use the tool: when the user wants recent public exchanges without authentication. It doesn't explicitly exclude alternatives like search or list_agents, but the context of 'recent' and 'public' provides clear usage direction. A slightly stronger contrast with siblings would earn a 5.

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