Phase 5 — Studio (Human-in-the-Loop Correction)

Goal: a web UI where humans can paste an address, see the parse, correct spans, and submit corrections. Corrections feed back into corpus retraining. This is the commercial differentiator — enterprises will pay for the ability to correct their own address data.

Status: deferred until Phase 3 has shipped and gathered usage. Do not begin Phase 5 without explicit confirmation.

This document is a sketch. Detailed plan will be written when Phase 5 begins.

Why this matters

• Address parsing has a long tail of locale-specific edge cases that no amount of pretraining catches
• Customers with their own address datasets (real estate, logistics, government compliance) need to fix model output for their data
• The studio is what turns a free library into a commercial product line

Sketch of components

Frontend

• React or Svelte (project creator's call)
• Paste address → see live parse with span boundaries
• Drag span edges to adjust boundaries
• Right-click span to relabel component
• Submit correction with optional notes

Backend

• Postgres table: corrections { id, raw, original_parse, corrected_parse, user_id, project_id, created_at, notes }
• API: POST /corrections, GET /corrections?project_id=...
• Auth: minimal — project tokens, no full user system v1

Retraining loop

• Nightly job: dump new corrections to /data/corpus/sources/corrections/
• Tag with high sample weight
• Trigger retraining (manual confirmation, not automatic — corrections can be adversarial)

What Phase 3 should leave in good shape

• ClassificationProposal carries enough info to round-trip through human correction
• The output format includes character offsets (it does) so span editing is mechanical
• Telemetry hooks exist to count "user accepted the parse as-is" vs "user corrected" — informs which components most need correction

Open questions for when Phase 5 begins

• Is this open source or commercial-only?
• How does the correction format become training data? (BIO labels need to be re-derived from corrected components)
• Quality gating: are all corrections trusted equally, or does each project's corrections only affect that project's model?
• Does the studio host its own model fine-tuned on the project's corrections?