5.2.14. Docling (Document Processor engine)

Docling is the engine behind the Document Processor role selectable via DOC_PROCESSOR_SOURCE. It is documented under the Document Processor aggregator rather than as a standalone service, because the user-facing role is "pick a doc-processing engine" — not "pick Docling":

→ See services/doc-processor/README.md for the full user-facing description, source-variant table, configuration reference, and integration notes.

1. Engine quick reference

• Image (GPU): pytorch/pytorch:2.13.0-cuda12.6-cudnn9-runtime (digest-pinned; used as BASE_IMAGE in the GPU provider Dockerfile); the provider requirements keep torch==2.13.0 and its matching torchvision==0.28.0 patch pair.
• License: MIT (IBM)
• Activation: DOC_PROCESSOR_SOURCE=docling-container-gpu (or docling-localhost for host-installed Docling)
• In-container port: 8000
• Host port: ${DOC_PROCESSOR_PORT} (computed from BASE_PORT by the bootstrapper)
• Readiness: GET /health starts configured converter construction off the API event loop and returns 503 starting until it succeeds. Invalid pipeline or device configuration returns 503 unavailable; health reports the converter only and does not claim lazily loaded model artifacts.

The manifest (service.yml) and compose fragment (compose.yml) in this folder are the bootstrapper's source of truth for those values; treat this README as a pointer, not a duplicate of the aggregator doc.

2. Dependencies & Integrations

2.1. Current — Upstream (this service calls)

No upstream calls.

2.2. Current — Downstream (services that call this)

Service	Category
kong	infra
docling-lightrag-adapter	media
celery	agents
n8n	agents
backend	apps
jupyterhub	apps

2.3. Architecture diagram

Open the full-size diagram for a full-screen view.

2.4. Future — Missing pair integrations

No high-confidence opportunities identified.

2.5. Future — Candidate new services

No high-confidence opportunities identified.

2.6. Future — Unused features in this service

No high-confidence opportunities identified.