# Agent Task Handoff Receipt

> Agent Task Handoff Receipt is a paid API for AI agents from phion.systems, paid per call via x402, $0.003/call, status unknown (last checked 2026-09-14).

Validates and cryptographically signs a portable task handoff packet including scope, budget, and expiry for secure agent-to-agent delegation

## Facts

- Endpoint: POST https://phion.systems/v1/paid/trust/agent-task-handoff-receipt
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent-task-handoff-receipt-5058c808
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_49Yh15KtXcc5FVWig2KD8

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 agent-task-handoff-receipt-5058c808 -d '<json body>'
```

Example prompt: Before handing off the data-scraping subtask to the subagent, validate and sign the task handoff with a scope of 'web-scraping', a budget of $0.50, and an expiry of 30 minutes from now so I have a tamper-proof receipt.

## When to prefer this

Use this endpoint when an orchestrator agent needs to securely delegate a bounded task to a subagent and requires a cryptographically signed, portable receipt proving the handoff was valid, scoped, and budget-constrained — particularly in multi-agent pipelines where auditability, tamper-evidence, and downstream trust verification are required. Prefer this over ad-hoc task passing when compliance, spending controls, or agent accountability are priorities.

## Known failure modes

- Invalid or missing task definition causes validation rejection
- Budget value out of acceptable range returns an error
- Expired or malformed expiry timestamp fails validation
- Signature generation failure due to internal key unavailability
- Incomplete scope specification causes schema validation error
- Malformed input JSON returns a 400-level error

## How this service works

Validate and sign a portable task, scope, budget and expiry handoff

## Output

A cryptographically signed, portable receipt confirming the task handoff is valid, including the attested scope, budget ceiling, expiry timestamp, and a signature that downstream agents and auditors can verify to ensure the delegation was not tampered with.

## Request schema (JSON Schema)

```json
{
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "type": "object"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent-task-handoff-receipt-5058c808/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from phion.systems](https://www.zero.xyz/host/phion.systems/llms.txt)