# List signal types

The signal catalog: each type, which modes it has, what a row costs, and the parameters of its `signal` object. Read this before you build a search. `event_posts` is the old name of `events` and is answered as `events`.

The signal catalog: each type, which modes it has, what a row costs, and the parameters of its `signal` object. Read this before you build a search. `event_posts` is the old name of `events` and is answered as `events`.

## Authentication

Send `Authorization: Bearer gtk_…`. Create the key under **Connect assistant → API keys**. A missing, invalid or revoked key is **401**, including while this API is closed. A valid key while the API is closed for your organization answers **404**, the same body as an unknown path. Every response includes `FounderMCP-Api-Version` and `FounderMCP-Request-Id`.

## Response

- **`object`** `string` · **required** — Always `list`. One of: `list`.
- **`data`** `object[]` · **required** — One `signal_type` per type.
- **`data[].type`** `string` · **required** — The type key.
- **`data[].modes`** `string[]` · **required** — `raw`, `screened`, or both.
- **`data[].default_mode`** `string` · **required** — The mode used when a search leaves `mode` out.
- **`data[].cost`** `object` · **required** — Credits per delivered row. `raw` is `{ row_key, credits_per_row }` or null. `screened` is `{ exact_lead, just_outside_lead }` or null.
- **`data[].parameters`** `object` · **required** — JSON Schema of the `signal` object for this type.
- **`data[].limits`** `string[]` · **required** — What this signal cannot see.

## Credits

Free. Costs in `data[].cost` are what a later search charges per delivered row.

## Errors

- **401** `authentication_error` — The Authorization header is missing, or the key is unknown or revoked.
- **403** `permission_error` — API access is not part of your plan, or your account is suspended.
- **404** `not_found` — The endpoint does not exist.
- **429** `rate_limit_error` — More than 60 requests per minute, or more than 3 at the same time, on one key. Wait for the Retry-After header.
- **500** `internal_error` — Something went wrong on our side.

## Example

### cURL

```bash
curl "https://foundermcp.dev/api/v1/signals" \
  -H "Authorization: Bearer $FOUNDERMCP_API_KEY"
```

### JavaScript

```javascript
const response = await fetch('https://foundermcp.dev/api/v1/signals', {
  method: 'GET',
  headers: {
    Authorization: `Bearer ${process.env.FOUNDERMCP_API_KEY}`
  }
});
const body = await response.json();
```

### Python

```python
import json
import os
import urllib.request

request = urllib.request.Request(
    "https://foundermcp.dev/api/v1/signals",
    headers={
    "Authorization": f"Bearer {os.environ['FOUNDERMCP_API_KEY']}"
    },
    method="GET",
)
with urllib.request.urlopen(request) as response:
    body = json.load(response)
```

### Example response

```json
{
  "object": "list",
  "data": [
    {
      "type": "funding_raised",
      "object": "signal_type",
      "title": "Leads that raised funding",
      "modes": [
        "raw",
        "screened"
      ],
      "default_mode": "raw",
      "returns": "company",
      "cost": {
        "raw": {
          "row_key": "funding_company",
          "credits_per_row": 1
        },
        "screened": {
          "exact_lead": 20,
          "just_outside_lead": 5
        }
      }
    }
  ]
}
```