Enable or disable a userscript

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

readOnlyHint=false correctly signals mutation, and the description adds the key behavioral fact beyond annotations: disabling keeps the script installed but stops injection. It stops short of covering what happens on an unknown name/uuid or whether the change persists across sessions.

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?

Two sentences, front-loaded with the action, then identification, then the semantic note about disabled state. No filler and nothing could be removed without losing signal.

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 small 3-parameter toggle with no output schema, this covers action, identification, and the state semantics. Only the edge cases (unknown script, both identifiers supplied) are unaddressed, which are minor for this tool.

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 baseline is 3, but the description adds value by explaining the two mutually alternative identifiers (uuid vs @name) and sourcing the @name from browser_tampermonkey_list. It does not address precedence when both are supplied, nor behavior when neither optional identifier is given.

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 and resource: turn a userscript on/off in Tampermonkey, and names the underlying mechanism (modifyScriptOptions with {enabled}). It is trivially distinguishable from browser_tampermonkey_install and browser_tampermonkey_remove, which change installation state rather than the enabled flag.

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 concrete routing guidance: identify the script by uuid, or by the @name obtained from browser_tampermonkey_list. It does not explicitly say when to prefer this over removal/reinstall, but the enabled-vs-installed framing makes that distinction implicit and clear.

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