host_services_discover

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

No annotations are provided, so the description carries the full burden, and it does disclose 'Read-only' plus the exact return format (ready services:/apps: YAML for fleet.yaml) — valuable given there is no output schema. It does not discuss permissions, rate limits, or how a partial/failed discovery behaves, leaving a minor gap.

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?

A single dense sentence that front-loads the discovery scope, then the return format, then the read-only/one-time usage note. The parenthetical asides are informative rather than wasteful, though the breadth of listed service types makes it slightly heavy.

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 read-only, one-parameter tool with no output schema and no annotations, the description compensates well by explaining both what is discovered and the shape of the returned YAML. Only minor gaps remain around error behavior and relationship to the other host_* discovery siblings.

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 is a single required parameter and schema description coverage is 100%, with the schema stating it is a host name from the inventory (fleet_hosts). The description adds no further parameter syntax or constraints, so the baseline of 3 is appropriate since the schema already does the work.

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 (discover) and resource (services running on a host), and scopes it precisely: docker compose projects, standalone containers, non-stock systemd services, and API-bearing apps. It distinguishes itself from the inventory (fleet_hosts) and from siblings like host_docker by enumerating exactly what it surfaces and what it returns (services:/apps: YAML for fleet.yaml).

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?

Gives a clear usage context: it finds what the inventory does not yet know, and 'use it to describe a home server once' frames it as a one-time discovery step. It stops short of naming alternatives or explicit when-not conditions (e.g. vs host_inspect or fleet_discover), so it lacks the exclusions that would earn a 5.

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