| name | htr-transcription |
| description | Transcribe handwritten historical documents with the HTRflow MCP tools — batch images into one htr_transcribe call and present the interactive viewer. Use when the user wants to transcribe or OCR handwriting, read old handwriting, or digitize a manuscript.
|
HTR Transcription
Transcribe handwritten historical documents using the HTRflow MCP server.
Returns an interactive viewer, per-line transcription JSON, and archival exports.
Tools
htr_transcribe — Transcribe images and return result URLs
Workflow
1. Determine image source
- http/https URLs (IIIF links, public image URLs): Use directly — skip to step 2.
- Local files or attachments: Must be uploaded first. Use the
/upload-files skill, then continue to step 2.
2. Transcribe
Call htr_transcribe once with ALL image URLs in a single call.
Batching rule: Never call htr_transcribe multiple times for separate
images. Each call runs an expensive GPU pipeline — batch everything.
3. Present results
After transcription, present results as an inline artifact for the viewer
and downloadable links for data exports.
4a. Inline viewer artifact
Download the viewer HTML, then inline all external dependencies (OpenSeadragon
JS and images) so the artifact is fully self-contained (the artifact sandbox
blocks external requests).
curl -sL "{viewer_url}" -o /home/claude/viewer.html
Then run this Python script to embed dependencies:
import re, base64, urllib.request
with open("/home/claude/viewer.html", "r") as f:
html = f.read()
osd_match = re.search(r'<script src="(https://cdn[^"]+openseadragon[^"]+)">\s*</script>', html)
if osd_match:
with urllib.request.urlopen(osd_match.group(1)) as resp:
osd_js = resp.read().decode()
html = html.replace(osd_match.group(0), f"<script>{osd_js}</script>")
for url in set(re.findall(
r'https://riksarkivet-htr-demo\.hf\.space/gradio_api/file=[^\s"]+\.(?:jpg|png)', html
)):
with urllib.request.urlopen(url) as resp:
img_data = resp.read()
ext = "jpeg" if url.endswith(".jpg") else "png"
data_uri = f"data:image/{ext};base64,{base64.b64encode(img_data).decode()}"
html = html.replace(url, data_uri)
with open("/mnt/user-data/outputs/viewer.html", "w") as f:
f.write(html)
Then call present_files with /mnt/user-data/outputs/viewer.html to render
the interactive viewer as an inline artifact.
4b. Export links
Provide the remaining URLs as clickable download links:
- Transcription data: [pages_url] (per-line JSON)
- Export: [export_url] (archival export)
Do NOT reproduce document text as plain text in your response — present
the artifact and links instead.
Options
Language
| Value | Use when |
|---|
swedish | Swedish handwriting (default) |
norwegian | Norwegian handwriting |
english | English handwriting |
medieval | Medieval scripts |
Layout
| Value | Use when |
|---|
single_page | Single pages, snippets, cropped regions (default) |
spread | Two-page book openings (Swedish only) |
Export format
| Value | Description |
|---|
alto_xml | ALTO XML — standard archival (default) |
page_xml | PAGE XML — alternative archival format |
json | JSON — structured data format |
Custom pipeline
custom_yaml accepts a raw HTRflow YAML config string. Overrides
language and layout. Use only when user explicitly provides one.
Example — English modern handwriting with a custom TrOCR model:
steps:
- step: Segmentation
settings:
model: yolo
model_settings:
model: Riksarkivet/yolov9-lines-within-regions-1
- step: TextRecognition
settings:
model: TrOCR
model_settings:
model: microsoft/trocr-base-handwritten
generation_settings:
batch_size: 16
- step: OrderLines