# draconic21 Signal Topic Trace

> draconic21 Signal Topic Trace is a paid API for AI agents from draconic21-x402-api.onrender.com, paid per call via x402, $0.06/call, status unknown (last checked 2026-10-12).

Traces the topic lineage or signal derivation path for a given subject within the draconic21 Daily Agent Signal system.

## Facts

- Endpoint: POST https://draconic21-x402-api.onrender.com/v1/signal_topic_trace?utm_source=zero.xyz
- Price: $0.06/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/draconic21-signal-topic-trace-9254fc79
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_X6d431qkra7-Uqo1qcJZt

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 draconic21-signal-topic-trace-9254fc79 -d '<json body>'
```

Example prompt: Can you trace the topic lineage for today's draconic21 daily signal — I want to see exactly which topics contributed to the signal output and how they connect?

## When to prefer this

Choose this endpoint when you need to understand the topic derivation path or lineage behind a draconic21 daily signal, rather than just fetching the signal value itself. Prefer this over signal_latest or signal_history when your goal is auditing, debugging, or researching which topics contributed to a signal output. At $0.06 per call it is priced above signal_latest ($0.03) but below signal_history ($0.10), appropriate for topic-level inspection tasks.

## Known failure modes

- HTTP 402 returned if payment is not provided or insufficient USDC balance
- Malformed request body returns 400 or validation error
- Empty or missing topic parameters may return an empty trace or error
- Service unavailability on Render hosting may cause 503 timeouts

## How this service works

GO-TO product for funded agents: Daily Agent Signal (POST /v1/signal_latest $0.03, /v1/signal_history $0.10, /v1/signal_delta $0.05). Signal is the flagship; supporting/legacy routes are demoted. Archive honesty: archive_day_count=6 — 6 stored dates from 2026-09-19 through 2026-09-27. Intraday revisions do not add archive days. Unpaid calls return HTTP 402. USDC on Base. Free discovery: /, /agents.md, /llms.txt, /skill.md, /.well-known/x402.json, /.well-known/mcp.json, /openapi.json.

## Output

Returns a JSON object with an 'ok' boolean indicating success, a 'brand' field set to 'draconic21', and a 'product' field confirming 'signal_topic_trace', along with any topic trace data showing how the signal's topic lineage is structured.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [],
     "properties": {},
     "additionalProperties": true
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "ok": {
       "type": "boolean"
      },
      "brand": {
       "type": "string"
      },
      "product": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "brand": "draconic21",
  "product": "signal_topic_trace"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/draconic21-signal-topic-trace-9254fc79/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from draconic21-x402-api.onrender.com](https://www.zero.xyz/host/draconic21-x402-api.onrender.com/llms.txt)