Detect wall materials

Wall material detection · model room-detector

POST/v1/drawings/detection/wall-materials

Detect rooms, derive wall segments, and resolve partition materials in a single async job. Runs room detection, detects wall segments, and matches each wall to a material with a confidence score — returning geometry, pattern_id, and material per wall in a slimmed-down result you poll for. Detections are in PDF coordinate space.

Returns: A job to check202 Accepted
Usage: Element detectionper sheet
Results in: A list of wallsresult.walls
Auth: API keyX-API-Key header

How it runs

Send a document_id
Get a job_id
Check your results or receive a webhook

Request

This endpoint requires a document_id. Upload your PDF first.

Body is JSON — this endpoint does not accept file uploads directly.

Field	Description
`document_id`string · UUIDRequired	ID of the uploaded PDF. Must belong to this account and not be expired.
`page_numbers`array of integersOptional	1-based page indices to run room detection on. Omit to scan all pages. Out-of-range values are skipped by the worker but still counted.
`floor_plan_pages`array of integersOptional	Subset of pages to derive walls on. Useful when you want rooms detected across the full set but walls derived only for a specific floor plan page. Defaults to page_numbers when omitted.
`webhook_url`string · URLOptional	URL to POST the completed job payload to. Delivered on developer, pro, and enterprise tiers only.

Header	Description
`X-API-Key`Required	Your API key. A missing or invalid key returns 401.
`Content-Type`Required	`application/json`

UsageUsage is counted on submission: each page in page_numbers (or every page of the document when omitted) is one element detection, not only the pages that contain rooms or walls. Send only valid page indices.

Responses

The job is enqueued immediately. Poll GET /v1/jobs/{job_id} until status is complete or failed.

Field	Description
`job_id`string · UUID	Use this to poll for results.
`status`string	Always queued on this response.
`poll_url`string	Path only — prepend `https://api.anchorgrid.ai` to build the full URL.

When status is complete and model is room-detector with derive_walls: true, the result field on the job contains:

Field	Description
`document_id`string	UUID of the source document.
`walls`array	Slimmed wall detections, one per derived wall segment.
`walls[].id`string	Stable wall identifier.
`walls[].room_id`string	ID of the room this wall segment belongs to.
`walls[].page`integer	1-based PDF page index where the wall was detected.
`walls[].line`object	Wall segment endpoints in PDF coordinate space: x1, y1, x2, y2.
`walls[].pattern_id`string \| null	Hatch cluster identifier. null when the wall was too short to sample.
`walls[].material`string	Resolved partition material (e.g. "1 HR FIRE BARRIER"). Present only when resolved.
`walls[].match_confidence`number	Confidence score for the material match. Present only when material is present — omitted otherwise, not null.

This endpoint returns a deliberately minimal wall shape. Internal algorithm fields (geom_source, outward_normal, source, hough_sampled_subsegments, fallback_sampled_subsegments, pattern_segments, room-level diagnostics) are not exposed here. If you need the fuller diagnostic shape, use GET /detection/rooms/{room_job_id}/walls.

Usage & rate limits

Each page submitted is one element detection, counted at job submission (See pricing). Rate limit: tier RPM (5 / 60 / 120 / 300).

Plan	When the allowance is used up
`trial`	Trial allowance — `402 FREE_TIER_LIMIT_REACHED` when used up, `402 TRIAL_ENDED` once the trial is over.
`developer`	Monthly allowance, then overage up to your overage limit — `402 OVERAGE_LIMIT_REACHED` at the limit (`429 QUOTA_EXCEEDED` when the allowance is used up without overage billing).
`enterprise`	No allowance check.

Rate-limit 429s include retry_after_seconds in the body. Quota 429s and rate-limit 429s return the same status code — check the error body to distinguish them.

Errors

Status	What it means
401	Missing or invalid X-API-Key.
402	Trial allowance used up.
404	document_id not found or expired.
422	Validation error — malformed UUID or invalid body.
429	Rate limit or monthly quota exceeded.

Examples

curl -X POST https://api.anchorgrid.ai/v1/drawings/detection/wall-materials \
  -H "X-API-Key: <your-api-key>" \
  -H "Content-Type: application/json" \
  -d '{
    "document_id": "550e8400-e29b-41d4-a716-446655440000",
    "page_numbers": [1, 2, 3],
    "floor_plan_pages": [3]
  }'

Response · 202

{
  "job_id": "7c9e6679-7425-40de-944b-e07fc1f90ae7",
  "status": "queued",
  "poll_url": "/v1/jobs/7c9e6679-7425-40de-944b-e07fc1f90ae7"
}

Completed job · result

{
  "document_id": "550e8400-e29b-41d4-a716-446655440000",
  "walls": [
    {
      "id": "wall_4f2a1c9be731",
      "room_id": "room_0091ab",
      "page": 3,
      "line": {
        "x1": 120.5,
        "y1": 340.2,
        "x2": 480.1,
        "y2": 340.2
      },
      "pattern_id": "pat_cluster_02",
      "material": "1 HR FIRE BARRIER",
      "match_confidence": 0.91
    }
  ]
}