{
  "id": "pdf-compress-pipeline",
  "name": "PDF Compression Pipeline",
  "version": "1.0.0",
  "description": "End-to-end workflow: fetch → choose tool → compress → validate → return",
  "trigger": {
    "type": "http",
    "method": "POST",
    "path": "/api/pdf-compress"
  },
  "steps": [
    {
      "id": "fetch",
      "name": "Fetch Source PDF",
      "description": "Resolve source to local path. Supports local path, https://, s3://",
      "module": "service.fetcher",
      "function": "resolve",
      "inputs": ["request.source"],
      "outputs": ["input_path", "is_temporary"]
    },
    {
      "id": "strategy",
      "name": "Select Tool Chain",
      "description": "Inspect file size and profile to determine best tool sequence",
      "module": "service.strategy",
      "class": "CompressionStrategy",
      "method": "select_chain",
      "inputs": ["input_path", "profile_dict"],
      "outputs": ["tool_chain"]
    },
    {
      "id": "compress",
      "name": "Run Compression",
      "description": "Execute tool chain, stop on first successful adapter",
      "loop": "tool_chain",
      "on_success": "validate",
      "on_failure": "next_in_chain"
    },
    {
      "id": "validate",
      "name": "Validate Output",
      "description": "Check PDF integrity, page count, and size improvement",
      "module": "service.validator",
      "function": "validate",
      "inputs": ["input_path", "output_path"],
      "outputs": ["validation_result"],
      "on_failure": "return_error"
    },
    {
      "id": "respond",
      "name": "Return Response",
      "description": "Build and return CompressResponse JSON",
      "outputs": ["ok", "original_size_bytes", "compressed_size_bytes", "ratio", "tool_chain", "output_path", "logs"]
    }
  ],
  "sequence_diagram": [
    "Agent            → POST /compress",
    "API (FastAPI)    → fetcher.resolve(source)",
    "API              → strategy.select_chain(input, profile)",
    "Strategy         → [ToolAdapter1, ToolAdapter2, ...]",
    "API              → adapter1.compress(input, output, profile)",
    "  adapter1       → subprocess (pdfsizeopt / gs / pdfEasyCompress)",
    "  adapter1       → CompressResult(ok, elapsed, stdout, stderr)",
    "API              → validator.validate(input, output)",
    "API              ← CompressResponse(ok, ratio, tool_chain, logs)"
  ]
}