Idempotency and Deterministic Retries

WAproxy enforces idempotent execution for wallet_send operations.

Each send request must include a unique idempotency identifier.

Header:
X-WAPROXY-IDEMPOTENCY: <unique_id>

The idempotency key guarantees that identical retries
do not create duplicate broadcasts.

Execution model:

If a request with the same idempotency key
has already been processed,
WAproxy returns the original result.

It does not rebroadcast.

Deterministic retry behavior ensures:

- safe network interruptions
- stable client retries
- no double-spend attempts
- predictable transaction history

Example:

wallet_id = w_xxxxx
to = bc1xxxx
amount_sat = 15000
idempotency_id = btc-send-001

If the client retries with the same parameters
and same idempotency_id,
WAproxy must return the same tx result.

If parameters differ under the same id,
execution must be rejected.

Idempotency is mandatory for safe execution under unreliable networks.

WAproxy guarantees deterministic transport
even under repeated requests.