FASTA validator

Open FASTA validator on Happytails.ai. This view has the same page content and links, with explicit tool capabilities. Read the processing notes before using a tool.

Tool capabilities

{
  "id": "fasta-validator",
  "category": "developer-tools",
  "built": true,
  "requirements": "Checks a strict FASTA profile with one header line beginning with >, a unique first-token identifier and a nonempty sequence for each record. DNA and RNA use separate IUPAC alphabets. Protein accepts the standard amino acids plus B, X, Z, J, U, O and *. Lowercase is accepted. Empty lines are ignored; sequence whitespace, digits, comments, mixed T/U and unsupported symbols are reported with line and column. Optional gaps are literal -. This is format validation, not a GenBank submission check or biological quality assessment. Runs locally without uploads or database lookup. Limit: 500000 combined input characters, 2000 records, 2000 validation issues, a 1000-symbol motif, 20000 matches and 10000000 symbol comparisons. Exceeding a limit rejects the complete report. Each export is limited to 3000000 characters; typed CSV allows 200000 values. Preview shows 200 rows. Processing stops after 10 seconds.",
  "implementation": {
    "fields": [
      {
        "key": "alphabet",
        "label": "Sequence alphabet",
        "value": "dna",
        "type": "select",
        "values": [
          "dna",
          "rna",
          "protein"
        ]
      },
      {
        "key": "allowGaps",
        "label": "Allow alignment gaps (-)",
        "value": "false",
        "type": "select",
        "values": [
          "false",
          "true"
        ]
      }
    ],
    "registrationFamily": "sequence-tools",
    "presentation": "metrics",
    "note": "Checks a strict FASTA profile with one header line beginning with >, a unique first-token identifier and a nonempty sequence for each record. DNA and RNA use separate IUPAC alphabets. Protein accepts the standard amino acids plus B, X, Z, J, U, O and *. Lowercase is accepted. Empty lines are ignored; sequence whitespace, digits, comments, mixed T/U and unsupported symbols are reported with line and column. Optional gaps are literal -. This is format validation, not a GenBank submission check or biological quality assessment. Runs locally without uploads or database lookup. Limit: 500000 combined input characters, 2000 records, 2000 validation issues, a 1000-symbol motif, 20000 matches and 10000000 symbol comparisons. Exceeding a limit rejects the complete report. Each export is limited to 3000000 characters; typed CSV allows 200000 values. Preview shows 200 rows. Processing stops after 10 seconds.",
    "inputMaxLength": 500000,
    "inputErrorCode": "SEQUENCE_INPUT",
    "example": {
      "input": ">sample unchanged description\nACGTrynACGT\n",
      "options": {
        "alphabet": "dna",
        "allowGaps": "false"
      }
    },
    "experience": {
      "automatic": false,
      "single": false,
      "inputMaxLength": 500000,
      "inputMode": "text",
      "label": "Your text",
      "placeholder": "Type or paste your input…",
      "help": "Up to 500,000 characters. Review the settings before running.",
      "helpParts": [
        "Up to 500,000 characters.",
        "Review the settings before running."
      ],
      "action": null
    },
    "mode": "explicit",
    "interactive": false
  },
  "execution": "Browser interface",
  "api": null,
  "browser_agent": {
    "supported": true,
    "name": "run_current_tool",
    "discovery": "WebMCP on the human page in a supporting browser",
    "verification": "See audit/API-AUDIT.md; availability is not verification"
  }
}

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