Get rule source (YAML)

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

readOnlyHint=true already covers the safety profile, and the description adds genuinely useful behavior beyond it: that the return includes parsed rules and an editability flag, and the demo-domain copy semantics. It stops short of describing freshness, size, or error behavior for unknown domains.

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?

Three short sentences, front-loaded with the primary outcome before the usage cue. The final demo-domain sentence is a little convoluted ('your own copy's rules once you have edited it, otherwise the shared demo's') but still earns its place by explaining a non-obvious behavior.

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?

An output schema exists, so return shape need not be spelled out, and the description rightly focuses on behavior and sequencing. Given a single trivial parameter, the only real omission is any hint about valid domain values, which keeps this just short of complete.

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 one required parameter, 'domain', with 0% schema description coverage, so the schema adds nothing and the description must compensate. The description only obliquely implies what a domain is (via the demo-domain sentence) and never clarifies naming format or where to discover valid domains.

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 ('Fetch') and resource ('a domain's rule set as editable YAML') and enumerates what comes back (parsed rules, edit permission). It partially differentiates from siblings by emphasizing editable source YAML, but never explicitly contrasts with list_rules, so an agent must still infer which of the two rule-retrieval tools it wants.

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 an explicit sequencing cue: 'Use this before `put_rules` to see the current rules', which clearly names the downstream tool this complements. It lacks any when-not guidance or a named alternative (e.g. list_rules) for read-only inspection.

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