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crw-migrate

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Coming from Firecrawl? Switch to fastCRW in one line. Use when the user has existing Firecrawl SDK code (firecrawl-py, firecrawl-js, REST calls, or an MCP config) and wants to point it at fastCRW — managed or self-hosted. Covers the exact base_url swap, which endpoints are drop-in, which have gaps, and how to verify the switch worked.

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How to use this skill

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crw-migrate — Coming from Firecrawl?

Switch in one line. The v2 API is a drop-in for the official firecrawl-py v4 SDK and firecrawl-js — swap the base URL and keep your code.

When to use

  • You have existing Firecrawl SDK code or REST calls you want to repoint.
  • You're replacing a firecrawl-mcp-server entry in your MCP config.
  • You want to know exactly which Firecrawl endpoints are covered vs. which need adaptation.

The one-line swap

firecrawl-py v4 (Python SDK)

Managed fastCRW:

from firecrawl import FirecrawlApp

app = FirecrawlApp(
    api_url="https://api.fastcrw.com",
    api_key="crw_live_..."
)

Self-hosted fastCRW (default port 3000, no auth):

app = FirecrawlApp(
    api_url="http://localhost:3000",
    api_key="any"          # self-host ignores the key when auth is not configured
)

firecrawl-js (TypeScript/Node SDK)

import FirecrawlApp from "@mendable/firecrawl-js";

const app = new FirecrawlApp({
  apiUrl: "https://api.fastcrw.com",   // or "http://localhost:3000"
  apiKey: "crw_live_...",
});

REST / curl

Replace https://api.firecrawl.dev with https://api.fastcrw.com (or your self-hosted http://localhost:3000). Auth header stays the same: Authorization: Bearer <key>.

# Before
curl -X POST https://api.firecrawl.dev/v1/scrape \
  -H "Authorization: Bearer fc-..." \
  -H "Content-Type: application/json" \
  -d '{"url":"https://example.com","formats":["markdown"]}'

# After — change exactly two things: host + key
curl -X POST https://api.fastcrw.com/v1/scrape \
  -H "Authorization: Bearer crw_live_..." \
  -H "Content-Type: application/json" \
  -d '{"url":"https://example.com","formats":["markdown"]}'

Compatibility matrix

Drop-in endpoints (no code change needed)

EndpointNotes
POST /v1/scrapeFull markdown/html/links/json formats, onlyMainContent, waitFor, renderJs, includeTags/excludeTags
POST /v1/crawl + GET /v1/crawl/:id + DELETE /v1/crawl/:idAsync BFS crawl, polling shape matches
POST /v1/mapURL discovery
POST /v1/searchOwn search backend instead of Fire-engine; same response shape
POST /v2/scrapev2 surface with parsers field for PDFs
POST /v2/crawl + GET /v2/crawl/activev2 crawl
POST /v2/mapv2 map
POST /v2/searchv2 search
POST /v2/batch/scrapeBatch scrape
POST /v2/parsePDF → markdown (see gaps below)

Gaps — what needs adaptation

Firecrawl featurefastCRW equivalentAction
POST /v1/extract (standalone LLM extraction route)Supported. Async: returns a job id, poll GET /v1/extract/{id}. POST /v1/scrape with formats: ["json"] + jsonSchema also works inline for a single URL.None, but switch to polling if you port the route as-is.
POST /v1/extract multi-URL batchSupported. Pass urls: [...]; the cap is limits.maxExtractUrls on GET /v1/capabilities (default 50).None.
POST /v1/deep-researchNot implemented — cloud-only Firecrawl feature.No equivalent.
POST /v1/agent (Spark models)Not implemented.No equivalent.
/v2/parse — DOCX/XLSX/RTF/ODTPDF only. fastCRW uses pdf-inspector (no OCR).Keep Firecrawl for non-PDF docs, or convert to PDF first.
parsers: [{mode: "ocr"}]Accepted for wire-compat; degrades to text-layer extraction with a pdf_ocr_unsupported warning (no OCR engine).If OCR is required, keep Firecrawl.
MCP tool names firecrawl_*fastCRW MCP uses crw_* (see below).Update MCP config.
Fire-engine anti-botNot available. fastCRW uses LightPanda → Chrome stealth ladder.For heavy Cloudflare sites, test coverage; consider proxy pool.

jsonSchema alias

Firecrawl's /v1/extract uses extract.schema. fastCRW's /v1/scrape accepts both the jsonSchema top-level field and the extract.schema alias for closer Firecrawl parity:

{
  "url": "https://example.com",
  "formats": ["json"],
  "jsonSchema": {
    "type": "object",
    "properties": { "title": { "type": "string" } }
  }
}

Requires [extraction.llm] configured in config.toml (or CRW_EXTRACTION__LLM__API_KEY env var). See crw-self-host.

Switching your MCP config

Firecrawl MCP uses firecrawl-mcp-server; fastCRW's MCP server is crw-mcp. Tool names change from firecrawl_* to crw_*:

Firecrawl MCP toolfastCRW MCP tool
firecrawl_scrapecrw_scrape
firecrawl_crawlcrw_crawl
firecrawl_check_crawl_statuscrw_check_crawl_status
firecrawl_mapcrw_map
firecrawl_searchcrw_search
firecrawl_extractcrw_scrape with formats=["json"] + jsonSchema
—crw_parse_file (PDF upload; no Firecrawl MCP equivalent)

Claude Code — replace in ~/.claude/claude_desktop_config.json (or settings)

{
  "mcpServers": {
    "crw": {
      "command": "npx",
      "args": ["crw-mcp"],
      "env": {
        "CRW_API_URL": "https://api.fastcrw.com",
        "CRW_API_KEY": "crw_live_..."
      }
    }
  }
}

For self-hosted (no auth, no env needed):

{
  "mcpServers": {
    "crw": {
      "command": "npx",
      "args": ["crw-mcp"]
    }
  }
}

Embedded mode (npx crw-mcp with no CRW_API_URL) runs the engine in-process — zero server to stand up, ~6 MB RAM.

Verify the swap — checklist

Run these after pointing at fastCRW. Each should return "success": true:

# 1. Health check (no auth)
curl http://localhost:3000/health
# → {"status":"ok",...}

# 2. Basic scrape
curl -X POST "$CRW_API_URL/v1/scrape" \
  -H "Authorization: Bearer $CRW_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"url":"https://example.com","formats":["markdown"]}' | jq .success
# → true

# 3. Map (URL discovery)
curl -X POST "$CRW_API_URL/v1/map" \
  -H "Authorization: Bearer $CRW_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"url":"https://example.com"}' | jq '.data | length'
# → N (should be > 0)

# 4. Search (requires a search backend — managed always works; self-host needs sidecar)
curl -X POST "$CRW_API_URL/v1/search" \
  -H "Authorization: Bearer $CRW_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"query":"fastCRW scraper","limit":3}' | jq .success
# → true

# 5. Structured extraction (requires [extraction.llm] configured)
curl -X POST "$CRW_API_URL/v1/scrape" \
  -H "Authorization: Bearer $CRW_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "url":"https://example.com",
    "formats":["json"],
    "jsonSchema":{"type":"object","properties":{"title":{"type":"string"}}}
  }' | jq '.data.json'

Compare the data.markdown / data.metadata shape from your existing Firecrawl responses — the field names on the overlap surface (title, description, sourceURL, statusCode) match. A few metadata sub-fields diverge; inspect with jq .data.metadata if your code reads specific keys.

See also