update_config

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

With no annotations, the description carries the full behavioral burden and does notably well: it discloses a preview-by-default (dry-run) mode, the confirm gate for actual mutation, the side effect that some settings restart FTL, and a hard refusal for authentication settings. It omits any note on permissions/privilege requirements, but the destructive and side-effect profile is well covered.

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?

Four short sentences, front-loaded with purpose and a use-it-now example, then the gating and side-effect caveats. It is compact and every sentence adds information, though the run-on structure of the first sentence is slightly awkward.

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?

The tool has an output schema, so return-value explanation is unnecessary, and the description covers the mutation gate, side effects, and rejected inputs. An agent could call this correctly; only privilege requirements and value-format expectations for arbitrary elements are left unstated.

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 description coverage is 0%, so the description must compensate, and it explains all four parameters: element via the dns.upstreams example, value via the list example, confirm as the preview/apply gate, and restart as the FTL-restart deferral switch. Only the exact expected value type/format for arbitrary elements is left to inference.

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 specific verb and resource ("Set a Pi-hole setting") and anchors it with a concrete example (element='dns.upstreams', value=['9.9.9.9']), making the intent unambiguous. It does not explicitly contrast with name-siblings like add_config_item, remove_config_item, or get_config, so it falls short of full sibling differentiation.

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 communicates clear usage conditions: the call previews by default and only applies when confirm=true, restart=false defers the FTL restart, and webserver.api.* settings are refused outright. It never names an explicit alternative tool (e.g. get_config for reading), so it stops short of full when/when-not/alternatives guidance.

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