list_nodes

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

With no annotations, the description carries the full burden. It usefully discloses a scope boundary (executor/current-build data excluded) and hints that list_running_builds output is filtered through MCP_ALLOWED_JOBS, but says nothing about permissions, result size, or pagination for this call.

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 tight sentences, front-loaded with the core action and its returned fields, followed by the exclusion and the routing pointer. No filler.

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 zero-parameter read tool with no output schema and no annotations, the description supplies the essentials: what is listed, which fields matter, and what is deliberately omitted. Return shape and ordering remain unspecified, but that is a minor gap.

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?

Zero parameters, so there is nothing to document; the schema trivially covers the empty argument object. Baseline 4 applies.

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?

States a specific verb and resource ('List build nodes') and names the attributes returned (capacity, idle and offline state). It distinguishes itself from the builds-oriented sibling list_running_builds, though it does not contrast with the single-node sibling get_node.

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?

Explicitly tells the agent what is out of scope ('Executor/current-build details are intentionally excluded') and routes to the named alternative ('use list_running_builds'). Clear condition for choosing the sibling, but no guidance on when list_nodes itself is preferred over get_node.

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