# Bounty Engineer Agent Handoff Capsule

> Bounty Engineer Agent Handoff Capsule is a paid API for AI agents from bounty-engineer-x402-prod.onrender.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-12).

Packages and serializes an agent's current execution state, completed steps, pending steps, blockers, and artifacts into a signed, verifiable handoff capsule for continuation or delegation.

## Facts

- Endpoint: POST https://bounty-engineer-x402-prod.onrender.com/v1/agent-handoff-capsule?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/bounty-engineer-agent-handoff-capsule-a2ba7394
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_XS05E4m5q971PSXoTzOZ7

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 bounty-engineer-agent-handoff-capsule-a2ba7394 -d '<json body>'
```

Example prompt: Save the current state of task t-42 — objective is 'Publish verified report', I've completed 'sources fetched', still need to 'validate output', no current blockers, and there's one artifact at https://example.com/report — and give me a signed handoff capsule I can pass to the next agent.

## When to prefer this

Choose this endpoint when an autonomous agent needs to checkpoint its execution state and hand off to another agent or resume later, especially when integrity verification (sha256) of the state snapshot is required. Prefer this over simple key-value state storage when you need a structured, versioned capsule format with explicit next_action routing, blocker tracking, and artifact references — particularly in multi-agent pipelines using the Bounty Engineer x402 infrastructure.

## Known failure modes

- Malformed input schema (missing required fields) returns validation error
- Exceeding maxItems limits on blockers (50), artifacts (60), pending_steps (100), or completed_steps (100) may cause rejection
- Payment failure via x402 protocol results in 402 response before processing
- Service unavailable on Render cold start causes timeout
- State field with non-serializable values may fail capsule construction

## How this service works

Machine-buyable infrastructure for autonomous agents: API cost routing, margin optimization, funding-rate data, webpage extraction, result verification, spend controls, retry planning, state, tender search and GitHub bounty intelligence.

## Output

Returns a JSON object with ok:true, a 'capsule' containing the serialized task state (objective, task_id, completed steps, pending steps, blockers, artifacts, state), a sha256 integrity hash of the capsule, a next_action field indicating what step to continue with, the capsule version string, and a limitations array describing what the endpoint does not invent or summarize.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "state": {},
  "task_id": {
   "type": "string"
  },
  "blockers": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "maxItems": 50
  },
  "artifacts": {
   "type": "array",
   "maxItems": 60
  },
  "objective": {
   "type": "string"
  },
  "pending_steps": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "maxItems": 100
  },
  "completed_steps": {
   "type": "array",
   "items": {
    "type": "string"
   },
   "maxItems": 100
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "mode": "agent_handoff_capsule",
  "capsule": {
   "state": {
    "attempt": 2
   },
   "pending": [
    "validate output"
   ],
   "task_id": "t-42",
   "version": "agent-handoff-v1",
   "blockers": [],
   "artifacts": [
    {
     "id": "report",
     "url": "https://example.com/report",
     "sha256": null
    }
   ],
   "completed": [
    "sources fetched"
   ],
   "objective": "Publish verified report"
  },
  "limitations": [
   "Packages caller-supplied state without inventing missing progress or summarizing hidden context."
  ],
  "next_action": {
   "type": "continue_step",
   "value": "validate output"
  },
  "capsule_sha256": "299645a615a75645e8fad78f9ab3f03a755d94fd3da0265c7b766754f0fe552e"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/bounty-engineer-agent-handoff-capsule-a2ba7394/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from bounty-engineer-x402-prod.onrender.com](https://www.zero.xyz/host/bounty-engineer-x402-prod.onrender.com/llms.txt)