host_list

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

Beyond the readOnlyHint and destructiveHint annotations, the description discloses useful behavioral detail: actual host resolution behavior when the environment variable is unset, the role of the `default` fallback, and the semantics of returned fields like `non_destructive (blocks destructive calls only)` and `tls`. It also notes the `docker-mcp://hosts` resource mirrors the tool, adding integration context. No contradiction with annotations.

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 front-loaded with the core purpose, then adds a dense but purposeful paragraph on host selection and a compact, structured return breakdown. Every sentence earns its place, and the format is easy to scan for an agent deciding whether to call the tool.

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-only tool, the description covers the source of hosts, selection semantics, default behavior, field meanings, and integration with host-scoped daemon tools. The return format is documented in enough detail that an agent can correctly interpret results and use them in subsequent calls. Nothing necessary 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?

This tool has zero parameters, so the input schema already covers all inputs and the 0-parameter baseline applies. The description adds relevant semantic context by explaining how each returned host `name` maps to the `host` argument used by other tools and what the `default` field means for omitted-host calls. That is valuable context beyond an empty 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 opens with 'List the Docker hosts configured via DOCKER_MCP_SERVER_HOSTS,' a specific verb plus resource. It further clarifies single-host versus multi-host resolution and the meaning of the `default` entry, making it easy to distinguish from configuration tools like context_list. The purpose is unambiguous and actionable.

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 clear context for when to use the tool, explaining that its entries are what the `host` argument selects from and that a returned `name` can be passed as the `host` argument to daemon-backed tools, with `system_ping(host=...)` as an explicit example. It does not explicitly state when-not-to-use or name a preferred sibling alternative, but it provides strong routing context.

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