Full lesson

agenttoll

ReceiptRail: on-chain delivery receipts for AI agent payments (x402/stablecoin). Plus the Agent/Chain Evidence Tools suite hub of read-only diagnostics CLIs.

What it does

From the project README:

[](https://github.com/xka0085-byte/agenttoll/actions/workflows/ci.yml) [](https://mcpservers.org/servers/xka0085-byte/agenttoll)

Original: xka0085-byte/agenttoll
SuperStack fork: Blockchains/agenttoll @ 88e2241
Stars: 0
Last push (original): 2026-10-09
Languages: JavaScript, HTML, Rust, Shell, Dockerfile
Detected stack: Anchorweb3.js
Categories: AI & Agents DeFi
Licence: MIT
Homepage: https://xka0085-byte.github.io/evidence-tools/

Architecture

8 source files. By extension: .rs ×8.

Top-level directory	Source files
`programs`	8

On-chain programs: programs/agenttoll

Dapp: devnet deploy pending

⏳ Devnet deploy pending — goes live when the devnet wallet is topped up. This fork's own dapp is not deployed yet, so there is no program address or transaction to show. It is queued in dapp-queue.txt; once devnet SOL is available it is deployed, exercised with real devnet transactions, and this section switches to the live dapp at /dapps/agenttoll/. Until then, the lesson and step-by-step guide below are complete, and you can run it locally with the commands below.

Key code, explained

Excerpts chosen automatically where the code uses the most Solana concepts, pinned to the fork's commit.

xka0085-byte/agenttoll · programs/agenttoll/src/instructions/verify_receipt.rs L1–24 @ 88e2241 · MIT · original

use anchor_lang::prelude::*; use crate::{constants::RECEIPT_SEED, error::AgentTollError, state::Receipt}; #[derive(Accounts)]#[instruction(report_id: String, digest: [u8; 32])]pub struct VerifyReceipt<'info> {    pub verifier: Signer<'info>,    #[account(        seeds = [RECEIPT_SEED, receipt.vendor.as_ref(), report_id.as_bytes()],        bump = receipt.bump    )]    pub receipt: Account<'info, Receipt>,} pub fn handle_verify_receipt(    ctx: Context<VerifyReceipt>,    report_id: String,    digest: [u8; 32],) -> Result<()> {    require!(ctx.accounts.receipt.report_id == report_id, AgentTollError::DigestMismatch);    require!(ctx.accounts.receipt.digest == digest, AgentTollError::DigestMismatch);    emit!(crate::ReceiptVerified {        verifier: ctx.accounts.verifier.key(),

Line 8 pub verifier: Signer<'info>,: Requires this account to have signed the transaction.
Line 10 seeds = [RECEIPT_SEED, receipt.vendor.as_ref(), report_id.as_bytes()],: Declares the PDA seeds. Anchor re-derives the address and rejects the account if it doesn't match.
Line 11 bump = receipt.bump: Uses the bump seed, the extra byte that pushes the derived address off the ed25519 curve.
Line 21 require!(ctx.accounts.receipt.report_id == report_id, AgentTollError::DigestMismatch);: An explicit validation that aborts the instruction with an error.
Line 23 emit!(crate::ReceiptVerified {: Emits an Anchor event that clients can parse from the logs.

xka0085-byte/agenttoll · programs/agenttoll/src/instructions/create_receipt.rs L1–24 @ 88e2241 · MIT · original

use anchor_lang::prelude::*; use crate::{constants::*, error::AgentTollError, state::Receipt}; #[derive(Accounts)]#[instruction(report_id: String, digest: [u8; 32])]pub struct CreateReceipt<'info> {    #[account(mut)]    pub vendor: Signer<'info>,    #[account(        init_if_needed,        payer = vendor,        space = 8 + Receipt::INIT_SPACE,        seeds = [RECEIPT_SEED, vendor.key().as_ref(), report_id.as_bytes()],        bump    )]    pub receipt: Account<'info, Receipt>,    pub system_program: Program<'info, System>,} pub fn handle_create_receipt(    ctx: Context<CreateReceipt>,    report_id: String,    digest: [u8; 32],

Line 9 pub vendor: Signer<'info>,: Requires this account to have signed the transaction.
Line 11 init_if_needed,: Creates the account only if it doesn't exist. Watch for re-initialisation bugs.
Line 14 seeds = [RECEIPT_SEED, vendor.key().as_ref(), report_id.as_bytes()],: Declares the PDA seeds. Anchor re-derives the address and rejects the account if it doesn't match.
Line 15 bump: Uses the bump seed, the extra byte that pushes the derived address off the ed25519 curve.

How to run, build and test

These commands come from the repo's own manifests (package.json scripts, Anchor.toml, Cargo, go.mod, Makefile). Check the README for prerequisites and environment variables.

Directory	Command	Runs
`receipts-service-deploy`	`npm run start`	node server.mjs
`receipts-service-deploy`	`npm run test`	node test/cross-verify.mjs
`receipts-service`	`npm run start`	node server.mjs
`receipts-service`	`npm run test`	node test/cross-verify.mjs
`.`	`anchor build`	compile programs and generate IDLs
`.`	`anchor test`	local validator + test suite
`.`	`anchor run test`	cargo test
`.`	`cargo build`	Rust workspace build
`.`	`cargo test`	Rust tests

What you could build from it

Fork the SuperStack copy and extend it within the AI & Agents gaps listed on the idea page.
Learn the pattern first: AI agents on Solana
Learn the pattern first: Building and sending transactions from a client