list_scriptsRetrieve installed JS hook scripts that run server-side in the goja VM to mutate HTTP requests and responses programmatically.
List installed JS hook scripts. Scripts run server-side in the engine's goja VM and can mutate any request/response programmatically.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful context about the resource itself (server-side execution in a goja VM, ability to mutate traffic), but says nothing about the tool's own behavior — ordering, what happens when no scripts are installed, or what is returned.
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 tight sentences, no filler, with the core action front-loaded. The second sentence is context rather than invocation guidance, but it earns its place by defining the resource the agent is listing.
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 zero-parameter list tool with no output schema, the description omits what each returned entry actually contains (script name, enabled state, scope/matchers) or whether results are ordered. Annotations cover safety and there are no params to document, so the gap is narrow but real.
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?
The tool takes zero parameters, so there is nothing for the description to disambiguate. The baseline for a parameterless tool is 4.
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: 'List installed JS hook scripts.' The second sentence clarifies what a script actually is (server-side goja VM code that mutates requests/responses), which meaningfully disambiguates it from siblings like list_rewrite_rules and list_mock_rules. It does not explicitly contrast itself with those siblings, so it falls short of a 5.
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?
No when-to-use, when-not-to-use, or alternative-tool guidance is given. The note that scripts 'mutate any request/response programmatically' hints at why one would care about scripts, but the agent is never told when to reach for this tool versus list_rewrite_rules, list_mock_rules, or list_chaos_rules.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.