list_spaces

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

No annotations are provided, so the description carries the burden. It discloses a limitation: some native EverMemOS Cloud spaces may not appear. It also clarifies the memory space concept and gives examples. It doesn't mention return structure or error scenarios, but for a list-only operation this is sufficient.

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 well-structured and every sentence adds value: main function, usage order, naming examples, caveat, fallback instruction. It's slightly long but not wasteful.

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 description is complete for a simple listing tool: it explains what spaces are, how to use the tool, what to watch out for, and what to do if empty. The lack of an output schema is mitigated by the clear 'List' semantics.

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?

Both parameters (limit, query) are fully described in the schema with 100% coverage. The description doesn't add syntax details, but it reinforces the purpose of discovering space IDs, which indirectly helps understand the query parameter. Baseline 3 is appropriate.

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 uses the specific verb 'List' and identifies the resource 'MCP-visible memory spaces.' It explicitly distinguishes from siblings by positioning it as the first call to discover space_id values before using other memory tools.

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?

Provides clear guidance: 'Call this first to discover which space_id values are available before using other memory tools.' It also explains the naming convention and gives a fallback action if no spaces exist, making usage boundaries clear.

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