# BeliefState Get Belief

> BeliefState Get Belief is a paid API for AI agents from beliefstate.ai, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-29).

Retrieves a specific analyst research belief (thesis, evidence, or outcome) by ID from the BeliefState platform, with optional pagination through supporting passages.

## Facts

- Endpoint: POST https://beliefstate.ai/v1/research/get_belief?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/beliefstate-get-belief-f6210e70
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_euyVCLNLNohIUVif7wKza

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 beliefstate-get-belief-f6210e70 -d '<json body>'
```

Example prompt: Pull the BeliefState research belief with ID 'eq-aapl-bullcase-2024' and show me the first supporting passage — I want the analyst thesis and evidence as of October 1st, 2024.

## When to prefer this

Use this endpoint when you already have a specific belief_id from BeliefState and need to retrieve the full analyst thesis, evidence passages, or outcome data associated with it. Ideal for AI trading agents that need to hydrate a known belief reference into full research content, or when paginating through multi-paragraph analyst reports. Prefer this over search-style endpoints when the belief identifier is already known.

## Known failure modes

- Invalid or unknown belief_id returns an error or empty result
- as_of date outside available data range may return no content
- paragraph_index or support_index out of bounds returns an error
- Malformed date-time format for as_of field causes validation failure
- Payment not included or insufficient USDC causes 402 Payment Required
- Rate limiting or quota exceeded returns an error response

## How this service works

The first AI-powered platform for top analyst research. Get theses from top analysts, dated evidence, and available outcomes for your AI.

## Output

Returns a JSON envelope containing schema_version, generated_at timestamp, and as_of timestamp, along with the full analyst belief content including thesis text, dated evidence passages, and available outcome data for the requested belief_id. Supports paginated access to supporting paragraphs and sub-passages via index fields.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input",
  "output"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [
      "belief_id"
     ],
     "properties": {
      "as_of": {
       "type": "string",
       "format": "date-time",
       "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z))$"
      },
      "belief_id": {
       "type": "string",
       "maxLength": 128,
       "minLength": 1
      },
      "support_index": {
       "type": "integer",
       "maximum": 9007199254740991,
       "minimum": 0,
       "description": "Source support within the selected paragraph; defaults to 0. Use next_support_index for another passage."
      },
      "paragraph_index": {
       "type": "integer",
       "maximum": 23,
       "minimum": 0
      },
      "support_text_offset": {
       "type": "integer",
       "maximum": 9007199254740991,
       "minimum": 0,
       "description": "UTF-16 offset within the selected supporting passage; defaults to 0. Use next_text_offset to continue its text."
      }
     },
     "additionalProperties": false
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "type": "string",
     "const": "POST"
    },
    "bodyType": {
     "type": "string",
     "const": "json"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type",
    "example"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "json"
    },
    "example": {
     "type": "object",
     "$comment": "Envelope excerpt only. Complete response schema: https://beliefstate.ai/v1/research/get_belief?schema=output",
     "required": [
      "schema_version",
      "generated_at",
      "as_of"
     ],
     "properties": {
      "as_of": {
       "type": "string",
       "format": "date-time"
      },
      "generated_at": {
       "type": "string",
       "format": "date-time"
      },
      "schema_version": {
       "type": "string",
       "const": "1"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "as_of": "2026-10-24T00:00:00.000Z",
  "generated_at": "2026-10-24T00:00:00.000Z",
  "schema_version": "1"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/beliefstate-get-belief-f6210e70/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from beliefstate.ai](https://www.zero.xyz/host/beliefstate.ai/llms.txt)