# Forrest classification of ulcer bleeding Forrest Status: LIVE Price: $0.005 USDC `GET /api/calc/forrest` HTML: https://magentlab.com/docs/forrest Markdown: https://magentlab.com/docs/forrest.md Not a medical device. Not a diagnosis, dose, or listing recommendation. ## What it computes Return the Forrest 1974 endoscopic lesion class (ia, ib, iia, iib, iic, or iii) and published description from a caller-assigned token. ## When to use When an agent already has an endoscopic Forrest class as assigned at endoscopy and needs the canonical token and 1974 lesion wording. magent does not interpret endoscopy images. Not Glasgow-Blatchford and not Rockall. ## When not to use - Not a medical device. - magent does not interpret endoscopy images. The caller assigns forrest as ia, ib, iia, iib, iic, or iii. - This tool is Forrest 1974 lesion class only. It does not report rebleeding percentages (Forrest 1974 does not publish them). Not Glasgow-Blatchford and not Rockall. ## Formula ``` forrest in {ia, ib, iia, iib, iic, iii} as assigned by the caller (Forrest 1974); Ia active spurting, Ib active oozing, IIa non-bleeding visible vessel, IIb adherent clot, IIc flat pigmented haematin / coffee-ground base, III clean ulcer base ``` ## Citation [Endoscopy in gastrointestinal bleeding](https://doi.org/10.1016/s0140-6736(74)91770-x) Forrest JA, Finlayson ND, Shearman DJ Lancet. 1974;2(7877):394-397 DOI: [10.1016/s0140-6736(74)91770-x](https://doi.org/10.1016/s0140-6736(74)91770-x) ## Worked example ### Forrest III clean ulcer base Given: `forrest=iii` 1. forrest iii → canonical iii 2. description is clean ulcer base / no signs of recent hemorrhage ## Also searched as - Forrest classification - Forrest class - endoscopic stigmata of recent hemorrhage - ulcer bleeding Forrest - Forrest 1974 - GI bleeding endoscopy class - Forrest Ia Ib IIa - stigmata of recent haemorrhage ## Parameters - `forrest` (string, required): Forrest 1974 endoscopic lesion class as assigned by the caller: ia (active spurting hemorrhage), ib (active oozing hemorrhage), iia (non-bleeding visible vessel), iib (adherent clot), iic (flat pigmented haematin / coffee-ground base), or iii (clean ulcer base / no signs of recent hemorrhage). Case-insensitive. magent does not interpret endoscopy images. ## Bulk (POST) POST the same path with a JSON items array. The first item is the GET unit; each additional item is $0.002. Invalid items return HTTP 400 before settlement. Method: `POST /api/calc/forrest` Max items: 25 Price: unit_amount + extra_item_amount * (n - 1) (unit 5000 atomic, extra 2000 atomic) Status: PREVIEW - 1 to 25 items. Each item uses the same keys as the GET query parameters. - POST of 1 item costs the same as GET. Lists longer than 25: chunk into multiple POSTs. Extra items still execute; do not pad dummy rows. - The first invalid item fails the whole request (index in the 400 JSON). You are not charged. - HTTP 200 is {count, path, items}. Each items[i] is the GET 200 body for that row. - Catalog misses (empty matches, found=false) stay paid 200s inside that slot. - x402 resource URL is this path plus n and body_sha256. Browsers that prefer text/html get the same paywall as GET; Pay retries POST with the same items. Example request: ```json { "items": [ { "forrest": "iii" }, { "forrest": "iii" } ] } ``` Human paywall (two-item fixture): https://api.magentlab.com/paywall/bulk/forrest Example 200: ```json { "count": 2, "path": "/api/calc/forrest", "items": [ { "description": "Clean ulcer base / no signs of recent hemorrhage", "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Forrest JA, Finlayson ND, Shearman DJ", "doi": "10.1016/s0140-6736(74)91770-x", "id": "forrest-1974", "pmid": "4136718", "source": "Lancet. 1974;2(7877):394-397", "title": "Endoscopy in gastrointestinal bleeding" }, "formula": "forrest", "formula_expression": "forrest in {ia, ib, iia, iib, iic, iii} as assigned by the caller (Forrest 1974); Ia active spurting, Ib active oozing, IIa non-bleeding visible vessel, IIb adherent clot, IIc flat pigmented haematin / coffee-ground base, III clean ulcer base", "criteria": [ { "factor": "ia", "met": false }, { "factor": "ib", "met": false }, { "factor": "iia", "met": false }, { "factor": "iib", "met": false }, { "factor": "iic", "met": false }, { "factor": "iii", "met": true } ], "forrest": "iii" }, { "description": "Clean ulcer base / no signs of recent hemorrhage", "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Forrest JA, Finlayson ND, Shearman DJ", "doi": "10.1016/s0140-6736(74)91770-x", "id": "forrest-1974", "pmid": "4136718", "source": "Lancet. 1974;2(7877):394-397", "title": "Endoscopy in gastrointestinal bleeding" }, "formula": "forrest", "formula_expression": "forrest in {ia, ib, iia, iib, iic, iii} as assigned by the caller (Forrest 1974); Ia active spurting, Ib active oozing, IIa non-bleeding visible vessel, IIb adherent clot, IIc flat pigmented haematin / coffee-ground base, III clean ulcer base", "criteria": [ { "factor": "ia", "met": false }, { "factor": "ib", "met": false }, { "factor": "iia", "met": false }, { "factor": "iib", "met": false }, { "factor": "iic", "met": false }, { "factor": "iii", "met": true } ], "forrest": "iii" } ] } ``` ## Response fields - `formula` (string): forrest - `formula_expression` (string): Published Forrest 1974 class rule - `forrest` (string): Canonical lowercase class: ia, ib, iia, iib, iic, or iii - `description` (string): 1974 lesion wording for that class - `criteria` (array): Per-class rows with factor (ia, ib, iia, iib, iic, iii) and met; exactly one is met - `citation` (object): Forrest 1974 Lancet citation - `disclaimer` (string): Not-a-device notice ## Example JSON Frozen fixture. Not a live lookup. ```json { "description": "Clean ulcer base / no signs of recent hemorrhage", "disclaimer": "Not a medical device. Deterministic published-formula or published-code output for autonomous agents. A licensed clinician remains responsible for patient care and billing submissions.", "citation": { "authors": "Forrest JA, Finlayson ND, Shearman DJ", "doi": "10.1016/s0140-6736(74)91770-x", "id": "forrest-1974", "pmid": "4136718", "source": "Lancet. 1974;2(7877):394-397", "title": "Endoscopy in gastrointestinal bleeding" }, "formula": "forrest", "formula_expression": "forrest in {ia, ib, iia, iib, iic, iii} as assigned by the caller (Forrest 1974); Ia active spurting, Ib active oozing, IIa non-bleeding visible vessel, IIb adherent clot, IIc flat pigmented haematin / coffee-ground base, III clean ulcer base", "criteria": [ { "factor": "ia", "met": false }, { "factor": "ib", "met": false }, { "factor": "iia", "met": false }, { "factor": "iib", "met": false }, { "factor": "iic", "met": false }, { "factor": "iii", "met": true } ], "forrest": "iii" } ``` ## Errors - HTTP 400 `invalid_forrest`: forrest must be ia, ib, iia, iib, iic, or iii (Forrest 1974). Returned before settlement; you are not charged. - HTTP 400 `invalid_items`: POST body must be a JSON object with only an items array Returned before settlement; you are not charged. - HTTP 400 `invalid_item_count`: items must be an array of 1 to 25 objects Returned before settlement; you are not charged. - HTTP 400 `invalid_item`: each items entry must be a JSON object Returned before settlement; you are not charged. Shared HTTP 402 and 503: https://magentlab.com/docs/payments ## Related tools - [Glasgow-Blatchford score](https://magentlab.com/docs/glasgow-blatchford) — Compute the Blatchford 2000 Glasgow-Blatchford score from urea, haemoglobin, systolic BP, heart rate, and four clinical flags. - [Pre-endoscopy Rockall](https://magentlab.com/docs/rockall-pre) — Compute the Rockall 1996 pre-endoscopy (admission) score from age, heart rate, systolic blood pressure, and caller-assigned comorbidity after acute upper gastrointestinal haemorrhage. ## Payment Unpaid requests return HTTP 402 even if query parameters or POST items are missing or invalid, so CDP and agents can index the path. After a PAYMENT-SIGNATURE, invalid params return HTTP 400 JSON before settlement. magent does not charge. Fix the params, then request a new 402 quote for that complete URL. Catalog misses (empty matches, found=false) are valid paid 200s. - GET the tool with Accept: application/json (do not send Accept: text/html unless you want the human paywall). - HTTP 402 means you have not paid. Decode the base64 PAYMENT-REQUIRED header. HTTP 503 is not a new quote. - Sign accepts[0] (exact, EIP-3009) with validBefore = now + maxTimeoutSeconds (600 seconds), or accepts[1] (batch-settlement deposit/voucher) on product GET. Ping and POST {items} stay exact. Magent retries transient facilitator 429/5xx before answering. - Retry the same URL with PAYMENT-SIGNATURE (base64 JSON of accepted and payload). Magent attaches canonical extensions.bazaar on CDP verify/settle; echoing 402 bazaar is optional. - Success is HTTP 200 JSON plus PAYMENT-RESPONSE. exact settles before the tool. batch-settlement verifies (and deposit-settles) before the tool and commits the charge after HTTP 2xx. HTTP 503: retry the same PAYMENT-SIGNATURE. Mint a new exact nonce only after a new HTTP 402. - offered `exact` on eip155:8453: Fixed-price USDC on Base. The buyer authorizes the advertised amount (EIP-3009). magent settles before the tool runs (paymentFlow upfront). extra.assetTransferMethod=eip3009 extra.paymentFlow=upfront. - offered `batch-settlement` on eip155:8453: Payment-channel vouchers claimed later in batches. Exact stays accepts[0]. Same-path POST {items} is still exact. extra.assetTransferMethod=eip3009 extra.paymentFlow=authorization. - not offered `upto`: Not offered. Usage-based: buyer authorizes a ceiling, seller settles the actual amount after work. Reserved for a future metered tool. Not for current calculators or code search. Same-path POST {items} is still scheme exact: one EIP-3009 authorization for GET unit plus $0.002 per extra item. That is not x402 batch-settlement (payment channels / vouchers). Shared HTTP 402 and 503 table: https://magentlab.com/docs/payments Stdio MCP (one process per host): https://magentlab.com/docs/mcp ## Guarantees - HTTP 402 is unpaid, including a missing query. After PAYMENT-SIGNATURE, invalid parameters return HTTP 400 before settlement. You are not charged. HTTP 402 never includes the tool JSON. - exact: settlement finishes before the tool (paymentFlow upfront). batch-settlement: verify/deposit before the tool; chargedCumulativeAmount commits after HTTP 2xx. Uncertain or failed settlement fails closed (HTTP 503). Retry the same PAYMENT-SIGNATURE. - HTTP 402 is unpaid only. Do not sign a second authorization because of a 503. - Execution is timeout-bounded and concurrency-capped. - Calculator inputs are stored encrypted for allowlisted operators (Magent Console). They are not in public logs, SSH lookups, catalog, or rollups. Request logs store path without query.