host_setup

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

Annotations declare destructiveHint=true and the description does real work to qualify that: application goes 'through the snapshot/audit pipeline' and 'does not mean unrestricted overwrite of unmanaged files.' That is valuable context an agent would otherwise have to guess from a destructive hint. The only soft spot is that it doesn't spell out recoverability (e.g., rollback via snapshots) or that repeated application is not idempotent, both of which matter given idempotentHint=false.

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?

It is dense and front-loaded: purpose first, then routing, then mode semantics. The closing sentence enumerating return values ('planned changes, validation, manual steps, warnings, and write references') is largely redundant with the existing output schema and could be dropped.

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 four-parameter tool with full schema coverage and an output schema, the description covers the remaining unknowns: when to reach for it, what the mode flag changes, and how its write path is governed. Nothing an agent needs to invoke it 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?

Schema coverage is 100%, so host_id, force, max_chars, and max_lines are all already documented in the schema itself. The description restates the force semantics but adds no new meaning on format, host registry values, or how the two limit parameters interact beyond what the property descriptions say. Baseline 3 applies when the schema carries the load.

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 names a specific verb pair and resource: 'Plan or apply managed instruction configuration for a supported agent host.' It immediately scopes the tool by naming two siblings it is not ('use host_check to validate... and sync_instructions to refresh'), so an agent can pick correctly without opening any schema.

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?

It gives an explicit precondition ('use after project initialization'), two named alternatives with their distinct purposes, and a decision rule for the main parameter ('force=false returns a plan; force=true applies'). That is when-to-use, when-to-use-something-else, and how to choose mode in one place.

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