MCP tool reference

Connect once at https://api.pre.dev/mcp to use specification generation and browser automation. Setup instructions cover authentication and client configuration. Call tools/list after initialization for the live input schemas. GET /mcp/info is a human-readable service inventory; it is not the protocol’s tool-discovery method.

Tool inventory

Tool	Purpose	Result
`fast_spec`	Generate a concise specification	Text with artifact links or a `get_spec` handoff
`deep_spec`	Generate a detailed specification	Text with artifact links or a `get_spec` handoff
`get_spec`	Retrieve a specification and its status	Text and, on success, `structuredContent`
`list_specs`	Paginated specification history	Text and, for a nonempty page, `structuredContent`
`browser_agent`	Run browser tasks	Text summary or an async run ID
`browser_agent_get`	Retrieve browser task results	JSON text and `structuredContent`
`browser_agent_list`	Paginated browser history	Text and `structuredContent`

Generation and browser execution consume credits. Retrieval and listing do not launch new work. The server marks browser execution as potentially destructive because a task can click, submit forms, or change data on external sites.

fast_spec and deep_spec

Both tools accept the same parameters:

Parameter	Required	Type	Meaning
`executiveSummary`	Yes	String, minimum 10 characters	What to specify
`existingContext`	No	String	Existing code, stack, constraints, and architecture as text
`docURLs`	No	Array of URL strings	Reference documentation

{
  "executiveSummary": "Add CSV exports to the reporting dashboard.",
  "existingContext": "An existing TypeScript app with a reports API and organization-scoped access.",
  "docURLs": ["https://www.rfc-editor.org/rfc/rfc4180"]
}

These MCP tools do not take REST’s input, currentContext, file, or async fields. They may return before generation finishes. If the result provides a specification ID, call get_spec until its status is completed or failed. Generation results are text, not the REST SpecResponse JSON envelope. A progress notification reaching 100 does not replace a terminal status check.

get_spec

{ "specId": "507f1f77bcf86cd799439011" }

specId is required. Use the ID returned by generation or listing. A successful structuredContent contains specId and status; it may also include endpoint, created, executionTimeMs, progress, specUrl, predevUrl, output, and errorMessage. output is specification Markdown, preferring the coding-agent variant. Status is pending, processing, completed, failed, or unknown. Optional values may be absent while generation is running.

list_specs

Parameter	Type	Default	Values
`limit`	Number	`20`	`1`–`100`
`skip`	Number	`0`	Zero or greater
`endpoint`	String	All	`fast_spec`, `deep_spec`
`status`	String	All	`pending`, `processing`, `completed`, `failed`

For nonempty pages, structuredContent contains specs, total, hasMore, skip, and limit. Each entry uses specId, not REST’s _id. Use get_spec for the full body. An empty page returns a text-only result. There is no find_specs MCP tool; use REST search.

browser_agent

Parameter	Required	Type	Meaning
`tasks`	Yes	Nonempty array	One object per browser task
`concurrency`	No	Number, `1`–`20`	Parallel task allowance within this run; default `5`
`async`	No	Boolean	Return the run ID without waiting for results

Each task supports:

Field	Type	Meaning
`url`	String, required	Starting URL
`instruction`	String	Goal to accomplish
`input`	Object of string values	Form fields or other task inputs
`output`	JSON Schema	Expected output shape
`successCondition`	String	Natural-language completion condition
`mode`	`auto`, `extract`, `agent`	Automatic routing, schema extraction, or goal-driven navigation
`maxSteps`	Integer, `1`–`50`	Planning-iteration budget
`maxDurationSeconds`	Integer, `5`–`600`	Per-task execution budget in seconds

Limits apply to each task. Set explicit budgets for long flows; defaults can vary by task and execution mode. Your account’s in-flight limit also applies to the whole submission. Synchronous execution returns a text summary, which truncates task data. Retrieve browser_agent_get for full structured results. Async execution returns the ID in text so you can poll it. The MCP tool has no stream or idempotencyKey input. It emits live notifications during synchronous execution when the client supports them. See browser MCP examples.

browser_agent_get

{ "id": "507f1f77bcf86cd799439011", "includeEvents": false }

id is required; includeEvents is optional and defaults to false. structuredContent contains the browser run, including individual task outcomes and extracted data. Set includeEvents to true to retrieve timelines and screenshots.

browser_agent_list

Parameter	Type	Default	Values
`limit`	Number	`20`	`1`–`100`
`skip`	Number	`0`	Use a nonnegative offset
`status`	String	All	`processing`, `completed`

The structured result contains total and batches. Each batch has id, status, total, completed, and totalCreditsUsed. Unlike REST listing, this tool does not return hasMore; compare your offset and page length with total.

Notifications and errors

The server sends notifications/message with params: { level, logger, data }. Browser messages contain a task index and event details; large screenshot and DOM values can be elided. Specification messages report phases such as start, generating, and packaging. To receive notifications/progress, include a progressToken in the tools/call request’s _meta:

{
  "jsonrpc": "2.0",
  "id": 2,
  "method": "tools/call",
  "params": {
    "name": "browser_agent",
    "arguments": {
      "tasks": [{ "url": "https://example.com", "instruction": "Read the page heading." }]
    },
    "_meta": { "progressToken": "heading-run" }
  }
}

Browser failures return isError: true when the tool call itself fails. Specification tools can return an error in text without isError; inspect the content and retrieve the specification status where an ID is available. Disconnecting or cancelling notification delivery does not cancel the underlying browser run.

Deprecated aliases

Older name	Current name
`browser_task`	`browser_agent`
`browser_task_get`	`browser_agent_get`
`browser_task_list`	`browser_agent_list`

The aliases remain registered for compatibility. Use the current names in new integrations. Credits, proposal review, queue status, and live browser URL retrieval are available through REST rather than dedicated MCP tools.

​Tool inventory

​fast_spec and deep_spec

​get_spec

​list_specs

​browser_agent

​browser_agent_get

​browser_agent_list

​Notifications and errors

​Deprecated aliases