memory_list_rooms

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false. The description adds meaningful context beyond annotations: the distinction between owned and joined rooms, and that returned addresses are meant to be passed as the 'domain' parameter. This is more than a minimal read operation, so a 4 is appropriate.

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?

Two sentences, front-loaded with the action, includes an example, and every sentence adds value. No wasted words.

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?

The tool is a simple list operation with good annotations and no output schema. The description covers purpose, scope, the relationship to sibling tools, and a concrete use case, making it complete for the tool's complexity.

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 and the schema coverage is 100%, so the baseline is 4 per the rubric. The description references the 'domain' address output, which indirectly explains why no parameters are needed, but doesn't need to add anything beyond the schema.

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 a specific verb+resource: 'List the shared memory rooms you can use' and specifies scope (OWN + JOINED). It distinguishes from siblings by noting the rooms' addresses are for memory_write/memory_read and that this replaces create/re-join.

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?

Explicit use case is provided: 'Use this to RE-FIND a room in a new session' with an alternative explicitly named ('instead of having to create or re-join it'). This clearly guides when to use the tool.

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