MCP Workbench MCP Server

Overview Schema Source Related Servers Discussions Admin

generate_spec

Generate a YAML test spec by automatically discovering an MCP server's capabilities. Returns a ready-to-run spec for testing tools, resources, and prompts.

Instructions

Generate a YAML test spec by discovering the capabilities of an MCP server. Returns a ready-to-run spec.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "transport": "<transport>"
    },
    "name": "generate_spec"
  }
}

Input Schema

Name	Required	Description
`transport`	Yes	Transport type to use for connecting to the server
`url`	No	Server URL (required for streamable-http transport)
`command`	No	Command to launch the server (required for stdio transport)
`args`	No	Arguments to pass to the server command
`headers`	No	HTTP headers to send (e.g. Authorization)
`include`	No	Only include these capability types in the spec
`exclude`	No	Exclude these capability types from the spec
`depth`	No	Discovery depth: shallow (list only) or deep (call each tool/resource/prompt)
`timeoutMs`	No	Timeout in milliseconds (default: 30000)

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Mar 22, 2026

TDQS

B3.2/5.0

Behavior2/5

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

With no annotations provided, the description carries full burden for behavioral disclosure. It mentions discovering capabilities but omits critical details: that it will connect to the server, potentially execute calls (especially with depth='deep'), and that it returns a YAML spec. The actual behavior of initiating network connections and running discovery actions is not transparent.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences with no wasted words. The action and result are front-loaded. Every word adds value, and the structure is clear and direct.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness2/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given 9 parameters and no output schema, the description is too terse. It does not explain the discovery mechanism, how transport selection affects required parameters, or how the output spec is structured. An agent lacks the operational context needed to invoke the tool correctly, especially for complex scenarios like specifying headers or depth.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so baseline is 3. The description does not add parameter-specific semantics beyond what the schema already provides. It does not elaborate on how parameters like depth or include/exclude affect the generated spec.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description explicitly states the tool generates a YAML test spec by discovering MCP server capabilities and returns a ready-to-run spec. The verb 'generate' is specific, and the resource is clearly a test spec. It distinguishes from sibling tools (explain_failure, inspect_server, run_spec) which serve different purposes.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance on when to use this tool versus alternatives. The description does not mention prerequisites, when not to use it, or how it compares to siblings like inspect_server or run_spec. Agents must infer usage context from the name and schema alone.

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

Deploy Server