Use this service when you need this capability: detects likely bounded content types from inert text or base64 bytes using deterministic signatures and structural signals without execution.
0.005 USDC per call
x402 V2 exact payment on Base mainnet (eip155:8453) using USDC. The HTTP 402 challenge confirms the exact requirements before an authorized payment.
POST https://signalharness.ai/api/agent/services/content_type_detect/invokeDetects likely bounded content types from inert text or base64 bytes using deterministic signatures and structural signals without execution.
This service applies bounded processing to the supplied input. Review its schema, result fields, and limits for the exact supported capability.
| Field | Type | Required | Limits |
|---|---|---|---|
| text | string | Optional | Minimum length 1; Maximum length 65536 |
| base64 | string | Optional | Pattern: ^[A-Za-z0-9+/]*={0,2}$; Minimum length 1; Maximum length 65536 |
| declaredContentType | string | Optional | Minimum length 1; Maximum length 256 |
| filename | string | Optional | Minimum length 1; Maximum length 1024 |
{
"text": "{\"example\":true}"
}{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"type": "object",
"additionalProperties": false,
"minProperties": 1,
"maxProperties": 4,
"required": [],
"properties": {
"text": {
"type": "string",
"minLength": 1,
"maxLength": 65536
},
"base64": {
"type": "string",
"pattern": "^[A-Za-z0-9+/]*={0,2}$",
"minLength": 1,
"maxLength": 65536
},
"declaredContentType": {
"type": "string",
"minLength": 1,
"maxLength": 256
},
"filename": {
"type": "string",
"minLength": 1,
"maxLength": 1024
}
}
}Illustrative output from the canonical adapter fixture and schema. It is not a completed paid execution or a current live observation.
{
"detectedMime": "example",
"declaredMime": "example",
"charset": "example",
"confidence": "low",
"structuralSignals": [
"example"
],
"warnings": [
"Verify the caller-supplied data before relying on this result."
]
}{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"type": "object",
"additionalProperties": false,
"minProperties": 6,
"maxProperties": 6,
"required": [
"detectedMime",
"declaredMime",
"charset",
"confidence",
"structuralSignals",
"warnings"
],
"properties": {
"detectedMime": {
"type": "string",
"minLength": 1,
"maxLength": 256
},
"declaredMime": {
"type": "string",
"minLength": 0,
"maxLength": 256
},
"charset": {
"type": "string",
"minLength": 0,
"maxLength": 64
},
"confidence": {
"type": "string",
"enum": [
"low",
"medium",
"high"
],
"minLength": 3,
"maxLength": 6
},
"structuralSignals": {
"type": "array",
"minItems": 1,
"maxItems": 32,
"items": {
"type": "string",
"minLength": 1,
"maxLength": 128
}
},
"warnings": {
"type": "array",
"minItems": 0,
"maxItems": 32,
"items": {
"type": "string",
"minLength": 1,
"maxLength": 1024
}
}
}
}Timeout: 3000 ms. Full schemas are in OpenAPI.
This schema-valid request returns the canonical HTTP 402 challenge without executing the service. A payment-capable client validates the challenge, signs only with prior authority and budget, and retries the identical body.
curl -i -X POST https://signalharness.ai/api/agent/services/content_type_detect/invoke \
-H "Content-Type: application/json" \
--data '{"text":"{\"example\":true}"}'