Zotero List Libraries

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

With no annotations supplied, the description carries the full behavioral burden, and it delivers: it states the tool is read-only with no side effects, explains local vs. web mode data sources, and warns that the active library is not flagged in the output, telling the agent to track state from zotero_switch_library or the env var. This is rich, non-obvious behavioral context.

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 long but every sentence earns its place: purpose, scope, entry contents, workflow relationship, exclusion, mode differences, read-only guarantee, state caveat, and an example. It is front-loaded with the core list behavior and progressively adds operational details without redundancy.

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 parameterless list tool with an output schema, the description is complete: it covers mode-dependent behavior, the workflow with zotero_switch_library, the sibling alternative, side effects, and an important state-tracking caveat. Nothing an agent needs to invoke this tool correctly is missing.

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?

There are zero parameters and the schema already confirms that (100% coverage), so there is little semantic work for the description to do. The description still explicitly states "No parameters" and includes an example call, fully closing the loop; baseline 4 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 states a precise verb and resource: "List every Zotero library this MCP can address," and enumerates exactly what is included (personal library, group libraries, RSS feeds in local mode). It also explicitly differentiates from zotero_get_collections, so an agent can distinguish it from its nearest sibling without inspecting schemas.

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 gives concrete when-to-use guidance: use it to discover a library ID before calling zotero_switch_library, framing the two as a read-then-switch workflow. It also names the alternative (zotero_get_collections) when the user wants collections inside the current library, providing a clear exclusion.

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