# 4Ts Score Calculator for Heparin-Induced Thrombocytopenia (HIT) > 4Ts Score Calculator for Heparin-Induced Thrombocytopenia (HIT) is a paid API for AI agents from api.magentlab.com, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15). Computes the Lo 2006 4Ts pretest probability score for heparin-induced thrombocytopenia (HIT), returning a sum (0–8) and risk band (low/intermediate/high). ## Facts - Endpoint: GET https://api.magentlab.com/api/calc/four_ts - Price: $0.005/call - Payment: x402 - Status: unknown - Last checked: 2026-09-15 - Activations on Zero: 0 - Tags: x402 - Canonical page: https://www.zero.xyz/c/4ts-score-calculator-for-heparin-induced-thrombocytopenia-hit-b4d0b8f9 - Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_9-f69ICGYE7MBkSbSUKz5 Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently. ## How to call it through Zero Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`): ```sh zero fetch --capability 4ts-score-calculator-for-heparin-induced-thrombocytopenia-hit-b4d0b8f9 ``` Example prompt: Calculate the 4Ts HIT score for a patient where I'm assigning 2 points for thrombocytopenia, 1 point for timing, 2 points for thrombosis, and 1 point for other causes — what's the total and risk band? ## When to prefer this Use this endpoint when you need a fast, deterministic Lo 2006 4Ts score sum and risk band without building the arithmetic yourself. Prefer it over a generic LLM calculation when you need reproducible, auditable clinical scoring. It is not the HEP score and not an antibody assay interpreter — use a different tool for those. Best suited for clinical decision support pipelines where the calling agent or clinician has already assigned the four Lo 2006 point values. ## Known failure modes - Any of the four integer parameters (thrombocytopenia, timing, thrombosis, other_causes) missing → validation error - Values outside the 0–2 integer range for any parameter → likely rejection or unexpected behavior - Non-integer (float or string) inputs for score fields → schema validation failure - Caller incorrectly pre-grades platelet counts or timing — magent does not sanity-check clinical assignments, so miscoded inputs yield a valid but clinically wrong score ## How this service works 4Ts score (Lo 2006) for heparin-induced thrombocytopenia pretest probability. Four caller-assigned integers 0-2 (thrombocytopenia, timing, thrombosis, other causes) using the published table; magent sums only (max 8). Bands 0-3 low, 4-5 intermediate, and 6-8 high pretest probability. Not a diagnosis of HIT, not the HEP score, and not an antibody result. magent does not grade platelet counts or day of onset. ## Output Returns the integer sum of the four caller-assigned 4Ts components (range 0–8) and a risk classification band: 0–3 = low pretest probability, 4–5 = intermediate, 6–8 = high. Does not return a diagnosis, antibody result, or HEP score. ## Request schema (JSON Schema) ```json { "type": "object", "$schema": "https://json-schema.org/draft/2020-12/schema", "required": [ "input" ], "properties": { "input": { "type": "object", "required": [ "type", "method" ], "properties": { "type": { "type": "string", "const": "http" }, "method": { "enum": [ "GET", "HEAD", "DELETE" ], "type": "string" }, "headers": { "type": "object", "additionalProperties": { "type": "string" } }, "queryParams": { "type": "object", "required": [ "thrombocytopenia", "timing", "thrombosis", "other_causes" ], "properties": { "timing": { "type": "integer", "description": "Caller-assigned Lo 2006 timing points (0, 1, or 2). magent does not infer day of onset. 2: clear onset days 5-10, or <=1 day with prior heparin within 30 days. 1: consistent with days 5-10 but not clear; onset after day 10; or <=1 day with heparin 30-100 days ago. 0: fall too early without recent heparin." }, "thrombosis": { "type": "integer", "description": "Caller-assigned Lo 2006 thrombosis points (0, 1, or 2). 2: new thrombosis, skin necrosis, or acute systemic reaction after heparin bolus. 1: progressive/recurrent thrombosis, silent thrombosis, or erythematous skin lesions. 0: none." }, "other_causes": { "type": "integer", "description": "Caller-assigned Lo 2006 other (oTher) causes of thrombocytopenia (0, 1, or 2). More points = more HIT-like. 2: no other apparent cause. 1: possible other cause. 0: definite other cause." }, "thrombocytopenia": { "type": "integer", "description": "Caller-assigned Lo 2006 thrombocytopenia points (0, 1, or 2). magent does not grade platelet counts. 2: platelet fall >50% AND nadir >=20. 1: fall 30-50% OR nadir 10-19. 0: fall <30% OR nadir <10." } } } }, "additionalProperties": false }, "output": { "type": "object", "required": [ "type" ], "properties": { "type": { "type": "string" }, "example": { "type": "object" } } } } } ``` ## Response schema (JSON Schema) ```json { "type": "json", "example": { "path": "/api/calc/four_ts", "count": 2, "items": [ { "score": 0, "formula": "four_ts", "citation": { "id": "lo-2006", "doi": "10.1111/j.1538-7836.2006.01787.x", "title": "Evaluation of pretest clinical score (4 T's) for the diagnosis of heparin-induced thrombocytopenia in two clinical settings", "source": "J Thromb Haemost. 2006;4(4):759-765", "authors": "Lo GK, Juhl D, Warkentin TE, Sigouin CS, Eichler P, Greinacher A" }, "max_score": 8, "components": [ { "value": 0, "factor": "thrombocytopenia", "points": 0, "present": false }, { "value": 0, "factor": "timing", "points": 0, "present": false }, { "value": 0, "factor": "thrombosis", "points": 0, "present": false }, { "value": 0, "factor": "other_causes", "points": 0, "present": false } ], "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.", "four_ts_band": "0-3", "formula_expression": "4Ts = thrombocytopenia + timing + thrombosis + other_causes; each 0-2 caller-assigned from Lo 2006 table; pretest probability low 0-3, intermediate 4-5, high 6-8; max 8" }, { "score": 0, "formula": "four_ts", "citation": { "id": "lo-2006", "doi": "10.1111/j.1538-7836.2006.01787.x", "title": "Evaluation of pretest clinical score (4 T's) for the diagnosis of heparin-induced thrombocytopenia in two clinical settings", "source": "J Thromb Haemost. 2006;4(4):759-765", "authors": "Lo GK, Juhl D, Warkentin TE, Sigouin CS, Eichler P, Greinacher A" }, "max_score": 8, "components": [ { "value": 0, "factor": "thrombocytopenia", "points": 0, "present": false }, { "value": 0, "factor": "timing", "points": 0, "present": false }, { "value": 0, "factor": "thrombosis", "points": 0, "present": false }, { "value": 0, "factor": "other_causes", "points": 0, "present": false } ], "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 su … (truncated) ``` ## More - Live health (JSON, refreshed every minute): https://www.zero.xyz/c/4ts-score-calculator-for-heparin-induced-thrombocytopenia-hit-b4d0b8f9/health.json - [Zero catalog index](https://www.zero.xyz/llms.txt) - [Other services from api.magentlab.com](https://www.zero.xyz/host/api.magentlab.com/llms.txt)