# CoinCap RSI (Relative Strength Index)

> CoinCap RSI (Relative Strength Index) is a paid API for AI agents from rest.coincap.io, paid per call via x402, $0.004/call, status unknown (last checked 2026-09-14).

Returns the Relative Strength Index (RSI) technical indicator for a given cryptocurrency asset slug.

## Facts

- Endpoint: GET https://rest.coincap.io/v3/agentFriendly/ta/bitcoin/rsi
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/coincap-rsi-relative-strength-index-5e43e1f9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_GcKzXDKnr2hUz8uutY1De

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 coincap-rsi-relative-strength-index-5e43e1f9
```

Example prompt: What's the current RSI for Bitcoin on CoinCap? I want to know if it's overbought or oversold right now.

## When to prefer this

Choose this endpoint when you need a pre-computed RSI technical indicator for a specific cryptocurrency without doing your own time-series math. It is ideal for trading bots, portfolio monitoring agents, or financial dashboards that need momentum signals quickly. Prefer this over raw price history endpoints when you want a ready-to-use RSI value rather than computing it yourself from OHLCV data.

## Known failure modes

- Invalid or unknown asset slug returns an error or empty result
- Network timeout if CoinCap servers are temporarily unavailable
- Insufficient historical price data for a newly listed asset may prevent RSI computation
- Payment failure (x402) if USDC balance is insufficient or payment is not properly submitted
- Rate limiting if too many requests are made in a short window

## How this service works

Relative strength index (RSI) for an asset slug.

## Output

Returns the RSI (Relative Strength Index) value for the specified cryptocurrency asset slug. RSI is a momentum oscillator ranging from 0 to 100, where values above 70 typically indicate overbought conditions and values below 30 indicate oversold conditions. The response includes the computed RSI figure and likely associated metadata such as the asset slug and timestamp.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "pathParams": {
     "type": "object",
     "required": [
      "slug"
     ],
     "properties": {
      "slug": {
       "type": "string"
      }
     }
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/coincap-rsi-relative-strength-index-5e43e1f9/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from rest.coincap.io](https://www.zero.xyz/host/rest.coincap.io/llms.txt)