DenialPath

Scrub a claim against the NCCI procedure-to-procedure (PTP) edits and medically unlikely edits (MUE) in force on its date of service. Deterministic: no model, so identical input always returns an identical verdict. Every finding.status is one of pass (checked against a real edit and clean), fail (an edit fires), bypassed (an edit fires but a modifier already on the line legitimately resolves it), or no_data (we hold no edit for this code or pair in our dataset). no_data is NOT a pass: treat it as unchecked, since CMS may still deny the line under an edit outside our loaded subset. summary.clean is true only when every finding is pass and none are no_data - never report a claim clean because nothing failed if some lines were never checked. The response echoes editQuarter (the CMS quarter version the verdict was computed against) and coverage (how many PTP pairs and MUE codes are loaded), so you can tell a caller exactly what was checked. Free, no API key needed; a key only raises the rate limit.

{
  "type": "object",
  "properties": {
    "dateOfService": {
      "type": "string",
      "format": "date",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
      "description": "ISO yyyy-mm-dd, e.g. \"2026-07-01\". Selects which CMS edit quarter applies."
    },
    "payerSlug": {
      "type": "string",
      "description": "Optional payer slug for context. Does not change the PTP/MUE verdict."
    },
    "lines": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "code": {
            "type": "string",
            "description": "CPT/HCPCS code, referenced numerically only, e.g. \"80053\"."
          },
          "modifiers": {
            "type": "array",
            "items": {
              "type": "string"
            },
            "description": "Modifiers on this line, e.g. [\"59\"]."
          },
          "units": {
            "type": "integer",
            "minimum": 1,
            "description": "Units billed on this line."
          }
        },
        "required": [
          "code",
          "units"
        ]
      },
      "minItems": 1,
      "maxItems": 500,
      "description": "The billed lines on this claim."
    }
  },
  "required": [
    "dateOfService",
    "lines"
  ]
}

Explain a CARC (Claim Adjustment Reason Code) and any RARCs (Remittance Advice Remark Codes) from a remittance: plain meaning, ranked corrective actions, and whether an appeal is worth filing. found:false means we do not hold that CARC in our dataset (X12 publishes far more codes than we have curated) - the response still returns the group-code meaning when a group prefix (CO/PR/OA/PI) was supplied, and note explains the gap rather than leaving it silent. unknownRarc reports, rather than silently drops, any RARC you passed that we do not hold. Passing payer additionally attaches that payer's appeal deadline where we hold one. Free, no API key needed.

{
  "type": "object",
  "properties": {
    "carc": {
      "type": "string",
      "description": "CARC code, with or without a group prefix, e.g. \"CO-45\" or \"45\"."
    },
    "rarc": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "description": "Optional RARC codes on the same remittance line."
    },
    "payer": {
      "type": "string",
      "enum": [
        "medicare",
        "medicaid",
        "aetna",
        "cigna",
        "unitedhealthcare",
        "anthem-bcbs",
        "bcbs-general",
        "humana",
        "kaiser-permanente",
        "tricare",
        "molina",
        "centene-ambetter",
        "oscar-health",
        "bright-health",
        "wellcare",
        "highmark",
        "horizon-bcbs",
        "independence-blue-cross",
        "emblemhealth",
        "health-net"
      ],
      "description": "Optional payer slug, to attach a timely-filing appeal deadline."
    }
  },
  "required": [
    "carc"
  ]
}

Look up NCCI procedure-to-procedure (PTP) edits, in two modes. Pair mode: pass column1, column2 (either order) and dateOfService to check whether that specific pair bundles on that date; status is no_data (we hold no edit for this pair in our dataset - NOT confirmation CMS has none), not_applicable (we hold the edit but it does not apply on this date, either outside its effective/deletion window or modifierIndicator "9" meaning the edit is deleted or never applicable), or applies. List mode: pass code alone to get every pair in the dataset involving that code, in either column, with no date filtering. modifierIndicator "0" means no modifier may ever bypass the edit; "1" means a modifier may bypass it, but only where the services were genuinely distinct. Free, no API key needed.

{
  "type": "object",
  "properties": {
    "column1": {
      "type": "string",
      "description": "Pair mode: a CPT/HCPCS code. Send with column2 and dateOfService. Column order does not matter; the response reports the pair in CMS column order."
    },
    "column2": {
      "type": "string",
      "description": "Pair mode: the other code in the pair."
    },
    "dateOfService": {
      "type": "string",
      "format": "date",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
      "description": "Pair mode, required: ISO yyyy-mm-dd, e.g. \"2026-07-01\". NCCI PTP edits are versioned quarterly, so a pair lookup cannot be answered without a date."
    },
    "code": {
      "type": "string",
      "description": "List mode: a single code. Returns every pair in the dataset involving it, in either column, with no date filtering."
    }
  },
  "oneOf": [
    {
      "title": "Pair mode: does this specific pair bundle on this date?",
      "required": [
        "column1",
        "column2",
        "dateOfService"
      ]
    },
    {
      "title": "List mode: every pair involving this code",
      "required": [
        "code"
      ]
    }
  ]
}

Look up the medically unlikely edit (MUE) unit limit for a single CPT/HCPCS code. status is found or no_data; no_data means we hold no MUE value for this code in our dataset, not that CMS publishes none. When found, the returned limit.mai (adjudication indicator: "1" line edit - denies the excess units on the line; "2" date-of-service absolute - never payable above the limit on that date, not even on appeal; "3" date-of-service clinical - may be allowed above the limit with supporting documentation) governs what a biller can do above the limit, explained in limit.maiMeaning. Free, no API key needed.

{
  "type": "object",
  "properties": {
    "code": {
      "type": "string",
      "description": "CPT/HCPCS code, e.g. \"36415\"."
    }
  },
  "required": [
    "code"
  ]
}

Generate an appeal letter for a denial, assembled deterministically from cited facts. REQUIRES A PRO OR SCALE PLAN. Called by an anonymous caller or a key on the free plan, this returns an upgrade_required error naming the pricing page - it never fabricates or partially generates a letter for a caller who cannot access the feature. The letter argues the billing question only: it never asserts anything about the patient's clinical condition. Any fact only the practice holds (providerName, claimNumber, dateOfService, codes, the signature) that is not supplied is rendered as an explicit "[TO BE COMPLETED BY PRACTICE]" placeholder in the letter body and listed by name in placeholders, never invented. grounded is true only when we hold the CARC supplied and could argue it with our own corrective-action data; when false, the letter still assembles around payer/claim details and any practiceNote given, but the substantive grounds section is left as a placeholder for the practice to write.

{
  "type": "object",
  "properties": {
    "carc": {
      "type": "string",
      "description": "CARC code from the remittance, e.g. \"CO-45\" or \"45\"."
    },
    "rarc": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "description": "Optional RARC codes on the same remittance line."
    },
    "payerSlug": {
      "type": "string",
      "enum": [
        "medicare",
        "medicaid",
        "aetna",
        "cigna",
        "unitedhealthcare",
        "anthem-bcbs",
        "bcbs-general",
        "humana",
        "kaiser-permanente",
        "tricare",
        "molina",
        "centene-ambetter",
        "oscar-health",
        "bright-health",
        "wellcare",
        "highmark",
        "horizon-bcbs",
        "independence-blue-cross",
        "emblemhealth",
        "health-net"
      ],
      "description": "Optional payer slug, to cite that payer's appeal policy and window."
    },
    "providerName": {
      "type": "string",
      "description": "Optional. Rendered as a placeholder if omitted."
    },
    "claimNumber": {
      "type": "string",
      "description": "Optional. Rendered as a placeholder if omitted."
    },
    "dateOfService": {
      "type": "string",
      "format": "date",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
      "description": "Optional, ISO yyyy-mm-dd. Rendered as a placeholder if omitted."
    },
    "codes": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "description": "Optional procedure codes at issue, numeric reference only."
    },
    "practiceNote": {
      "type": "string",
      "description": "Optional free-text detail from the practice, appended to the argument section."
    }
  },
  "required": [
    "carc"
  ]
}

Days remaining to file an initial claim (or, if already past, how far over) for a payer given a date of service. daysRemaining and expired are null when we hold no published timely filing limit for that payer, which is common since many limits are contract-specific - check note before treating the result as an actual deadline. Free, no API key needed.

{
  "type": "object",
  "properties": {
    "payer": {
      "type": "string",
      "enum": [
        "medicare",
        "medicaid",
        "aetna",
        "cigna",
        "unitedhealthcare",
        "anthem-bcbs",
        "bcbs-general",
        "humana",
        "kaiser-permanente",
        "tricare",
        "molina",
        "centene-ambetter",
        "oscar-health",
        "bright-health",
        "wellcare",
        "highmark",
        "horizon-bcbs",
        "independence-blue-cross",
        "emblemhealth",
        "health-net"
      ],
      "description": "Payer slug, e.g. \"aetna\"."
    },
    "dateOfService": {
      "type": "string",
      "format": "date",
      "pattern": "^\\d{4}-\\d{2}-\\d{2}$",
      "description": "ISO yyyy-mm-dd, e.g. \"2026-01-15\"."
    }
  },
  "required": [
    "payer",
    "dateOfService"
  ]
}