# BeliefState Research Belief Search

> BeliefState Research Belief Search is a paid API for AI agents from beliefstate.ai, paid per call via x402, $1.5/call, status unknown (last checked 2026-10-29).

Searches a curated database of top analyst investment theses (beliefs) with optional filtering by ticker, direction, status, time horizon, and date

## Facts

- Endpoint: POST https://beliefstate.ai/v1/research/search_beliefs?utm_source=zero.xyz
- Price: $1.5/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/beliefstate-research-belief-search-c3befe0d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_SJ8B7S3zPioXr26xklQ7J

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-research-belief-search-c3befe0d -d '<json body>'
```

Example prompt: Search BeliefState for active bullish analyst theses on TSLA, and show me up to 10 results with their evidence and outcomes.

## When to prefer this

Use this endpoint when you need to discover or filter analyst investment theses at scale — especially when you want to narrow by ticker, directional bias (bullish/bearish), belief status (active, strengthened, reversed), or recency of change. Prefer this over broader research endpoints when you want structured belief objects with evidence and outcomes rather than narrative summaries.

## Known failure modes

- Missing required query parameter 'q' on first page returns validation error
- Invalid date format for as_of or changed_since returns 400
- Unknown ticker or entity_id returns empty results rather than an error
- Cursor from a different search query returns unexpected results
- Rate limiting or payment failure returns 402 or 429
- Limit exceeding 50 returns schema validation error

## 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 paginated list of analyst belief objects, each containing the investment thesis, directional signal (bullish/bearish/etc.), current status (active/strengthened/weakened/etc.), supporting evidence with dates, available outcomes, associated ticker and entity, and analyst attribution. Includes pagination cursor for subsequent pages and an as-of timestamp.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input",
  "output"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "properties": {
      "q": {
       "type": "string",
       "maxLength": 2000,
       "minLength": 1,
       "description": "Thesis, topic or trade setup. Required on the first page."
      },
      "as_of": {
       "type": "string",
       "format": "date-time",
       "pattern": "^(?:(?:\\d\\d[2468][048]|\\d\\d[13579][26]|\\d\\d0[48]|[02468][048]00|[13579][26]00)-02-29|\\d{4}-(?:(?:0[13578]|1[02])-(?:0[1-9]|[12]\\d|3[01])|(?:0[469]|11)-(?:0[1-9]|[12]\\d|30)|(?:02)-(?:0[1-9]|1\\d|2[0-8])))T(?:(?:[01]\\d|2[0-3]):[0-5]\\d:[0-5]\\d(?:\\.\\d+)?(?:Z))$"
      },
      "limit": {
       "type": "integer",
       "maximum": 50,
       "minimum": 1
      },
      "cursor": {
       "type": "string",
       "maxLength": 2048,
       "minLength": 1,
       "description": "Use next_cursor for another page of the same search."
      },
      "status": {
       "enum": [
        "forming",
        "active",
        "strengthened",
        "weakened",
        "reversed",
        "resolved",
        "abandoned",
        "unknown"
       ],
       "type": "string"
      },
      "ticker": {
       "type": "string",
       "maxLength": 32,
       "minLength": 1
      },
      "direction": {
       "enum": [
        "bullish",
        "bearish",
        "mixed",
        "neutral",
        "non_directional",
        "unknown"
       ],
       "type": "string"
      },
      "entity_id": {
       "type": "string",
       "format": "uuid",
       "pattern": "^([0-9a-fA-F]{8}-[0-9a-fA-F]{4}-[1-8][0-9a-fA-F]{3}-[89abAB][0-9a-fA-F]{3}-[0-9a-fA-F]{12}|00000000-0000-0000-0000-000000000000|ffffffff-ffff-ffff-ffff-ffffffffffff)$",
       "description": "Released subject ID returned by search_entities."
      },
      "person_id": {
       "type": "string",
       "maxLength": 128,
       "minLength": 1
      },
      "time_horizon": {
       "type": "string",
       "maxLength": 128,
       "minLength": 1
      },
      "changed_since": {
       "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]
… (truncated)
```

## 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-research-belief-search-c3befe0d/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)