# Delx EVM Value Plus Fee Budget

> Delx EVM Value Plus Fee Budget is a paid API for AI agents from api.delx.ai, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-15).

Calculates the total Wei required to cover a given transaction value plus a capped fee, for EVM preflight budget checks.

## Facts

- Endpoint: POST https://api.delx.ai/api/v1/x402/evm-value-plus-fee-budget
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/delx-evm-value-plus-fee-budget-54e304b5
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_UgpWChDSoexQvmCPuxN7n

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 delx-evm-value-plus-fee-budget-54e304b5 -d '<json body>'
```

Example prompt: Before submitting my EVM transaction, calculate the total Wei I need if the transaction value is 50000000000000000 Wei and my fee ceiling is 42000000000000 Wei.

## When to prefer this

Use this endpoint when an AI agent needs to perform a preflight EVM budget calculation — specifically to determine the total Wei required for a transaction that includes both a value transfer and a fee cap — before submitting on-chain. It is stateless, runs in memory without data retention, and is purpose-built for autonomous agent workflows that need deterministic, bounded arithmetic on EVM Wei amounts without calling an external node.

## Known failure modes

- Invalid or non-numeric Wei string causes a validation error
- value_wei or fee_ceiling_wei exceeds maxLength of 8192 characters
- Missing required fields returns a schema validation error
- Extremely large Wei values may cause overflow or precision issues

## How this service works

EVM Value Plus Fee Budget: EVM Value Plus Fee Budget sums transaction value and fee ceiling for a funding requirement from bounded caller-supplied values without an external provider. Call EVM Value Plus Fee Budget before signing, submitting, replacing, or accepting an EVM/Base transaction assembled from caller-owned data. Returns normalized transaction evidence, calculated budget or shape findings, and a fail-closed preflight status for EVM Value Plus Fee Budget as versioned deterministic JSON…

## Output

Returns a JSON object with the original value_wei, the computed required_wei (value plus fee), and the fee_ceiling_wei used, along with a status of 'pass', the operation name, and an evidence block confirming no data was retained and no external calls were made.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "value_wei": {
   "type": "string",
   "maxLength": 8192,
   "description": "Value Wei supplied to EVM Value Plus Fee Budget; used only for this bounded calculation and processed in memory without retention."
  },
  "fee_ceiling_wei": {
   "type": "string",
   "maxLength": 8192,
   "description": "Fee Ceiling Wei supplied to EVM Value Plus Fee Budget; used only for this bounded calculation and processed in memory without retention."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "result": {
   "value_wei": "50000000000000000",
   "required_wei": "50042000000000000",
   "fee_ceiling_wei": "42000000000000"
  },
  "schema": "delx/util-evm-value-plus-fee-budget/v1",
  "status": "pass",
  "evidence": {
   "retained": false,
   "input_sha256": "c97960a555f73366664990411512e0dbb6ff9e788f1f8df5e0e28f4eb3bedeb6",
   "external_calls": 0
  },
  "operation": "evm_preflight:evm_value_plus_fee_budget"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/delx-evm-value-plus-fee-budget-54e304b5/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.delx.ai](https://www.zero.xyz/host/api.delx.ai/llms.txt)