> ## Documentation Index
> Fetch the complete documentation index at: https://docs.x0protocol.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Constants Reference

> Complete reference of all protocol constants used across x0 on-chain programs.

All protocol constants are defined in `x0-common` and shared across every on-chain program. Many are governance-adjustable via the wrapper's timelock mechanism.

## Program IDs

| Constant                | Value                                          | Description           |
| ----------------------- | ---------------------------------------------- | --------------------- |
| `ESCROW_PROGRAM_ID`     | `AhaDyVm8LBxpUwFdArA37LnHvNx6cNWe3KAiy8zGqhHF` | x0-escrow program     |
| `GUARD_PROGRAM_ID`      | `2uYGW3fQUGfhrwVbkupdasXBpRPfGYBGTLUdaPTXU9vP` | x0-guard program      |
| `REPUTATION_PROGRAM_ID` | `FfzkTWRGAJQPDePbujZdEhKHqC1UpqvDrpv4TEiWpx6y` | x0-reputation program |

## Protocol Identifiers

| Constant           | Value               | Description                    |
| ------------------ | ------------------- | ------------------------------ |
| `PROTOCOL_VERSION` | `"2.0"`             | Current protocol version       |
| `PROTOCOL_NAME`    | `"x0-01"`           | Protocol name for x402 headers |
| `NETWORK_MAINNET`  | `"solana-mainnet"`  | Mainnet network identifier     |
| `NETWORK_DEVNET`   | `"solana-devnet"`   | Devnet network identifier      |
| `NETWORK_LOCALNET` | `"solana-localnet"` | Localnet network identifier    |

## Fee Configuration

| Constant                        | Value    | Description                                        |
| ------------------------------- | -------- | -------------------------------------------------- |
| `PROTOCOL_FEE_BASIS_POINTS`     | `80`     | 0.8% protocol fee via TransferFee extension        |
| `MAX_PROTOCOL_FEE_BASIS_POINTS` | `1000`   | 10% governance safety cap                          |
| `MIN_PROTOCOL_FEE`              | `1`      | 1 micro-unit minimum fee (prevents dust avoidance) |
| `FEE_DENOMINATOR`               | `10,000` | Basis points denominator                           |

## Time Constants

| Constant                         | Value       | Human-Readable     | Description                       |
| -------------------------------- | ----------- | ------------------ | --------------------------------- |
| `ROLLING_WINDOW_SECONDS`         | `86,400`    | 24 hours           | Spending window duration          |
| `MAX_ROLLING_WINDOW_ENTRIES`     | `144`       | \~10 min intervals | Max entries in the rolling window |
| `BLINK_EXPIRY_SECONDS`           | `900`       | 15 minutes         | Blink expiration time             |
| `DEFAULT_ESCROW_TIMEOUT_SECONDS` | `259,200`   | 72 hours           | Default escrow timeout            |
| `MIN_ESCROW_TIMEOUT_SECONDS`     | `3,600`     | 1 hour             | Minimum escrow timeout            |
| `MAX_ESCROW_TIMEOUT_SECONDS`     | `2,592,000` | 30 days            | Maximum escrow timeout            |

## Slot-Based Time Constants

These constants protect against clock manipulation by using slot numbers instead of (or alongside) Unix timestamps.

| Constant                      | Value     | Approx. Time | Description                            |
| ----------------------------- | --------- | ------------ | -------------------------------------- |
| `SLOTS_PER_SECOND`            | `2`       | —            | Conservative estimate (400ms/slot)     |
| `ROLLING_WINDOW_SLOTS`        | `216,000` | \~24 hours   | Slot-based spending window with buffer |
| `TIME_CHECK_BUFFER_SLOTS`     | `750`     | \~5 minutes  | Clock skew safety margin               |
| `ESCROW_TIMEOUT_BUFFER_SLOTS` | `1,500`   | \~10 minutes | Escrow timeout safety margin           |

## Rate Limiting

| Constant                         | Value       | Description                                |
| -------------------------------- | ----------- | ------------------------------------------ |
| `MAX_BLINKS_PER_HOUR`            | `3`         | Maximum Blinks per agent per hour          |
| `BLINK_GENERATION_COST_LAMPORTS` | `1,000,000` | 0.001 SOL burned per Blink                 |
| `POLICY_UPDATE_COOLDOWN_SLOTS`   | `750`       | \~5 min between policy updates             |
| `ARBITER_RESOLUTION_DELAY_SLOTS` | `216,000`   | \~24 hour delay before arbiter can resolve |

## Policy Limits

| Constant              | Value               | Human-Readable | Description                    |
| --------------------- | ------------------- | -------------- | ------------------------------ |
| `MAX_DAILY_LIMIT`     | `1,000,000,000,000` | 1M tokens      | Maximum daily spending limit   |
| `MIN_DAILY_LIMIT`     | `1,000,000`         | 1 token        | Minimum daily limit            |
| `MIN_TRANSFER_AMOUNT` | `100`               | 0.0001 tokens  | Dust transfer prevention       |
| `DEFAULT_DAILY_LIMIT` | `100,000,000,000`   | 100K tokens    | Default limit for new policies |

## Whitelist Configuration

| Constant                    | Value    | Description                           |
| --------------------------- | -------- | ------------------------------------- |
| `MAX_MERKLE_WHITELIST_SIZE` | `10,000` | Max addresses in Merkle whitelist     |
| `MAX_MERKLE_PROOF_DEPTH`    | `14`     | log2(10,000) ≈ 14                     |
| `BLOOM_FILTER_SIZE_BYTES`   | `4,096`  | 4KB for \~1000 items at 1% FP rate    |
| `BLOOM_HASH_COUNT`          | `7`      | Number of Bloom filter hash functions |
| `MAX_DOMAIN_PREFIXES`       | `100`    | Max domain prefixes in Domain mode    |
| `DOMAIN_PREFIX_LENGTH`      | `8`      | Bytes per domain prefix               |

## PDA Seeds

| Constant                      | Seed                | Derivation                                     |
| ----------------------------- | ------------------- | ---------------------------------------------- |
| `AGENT_POLICY_SEED`           | `"agent_policy"`    | `[seed, owner.key()]`                          |
| `ESCROW_SEED`                 | `"escrow"`          | `[seed, buyer.key(), seller.key(), memo_hash]` |
| `REGISTRY_SEED`               | `"registry"`        | `[seed, agent_id.key()]`                       |
| `REPUTATION_SEED`             | `"reputation"`      | `[seed, agent_id.key()]`                       |
| `PROTOCOL_CONFIG_SEED`        | `"protocol_config"` | `[seed]`                                       |
| `TREASURY_SEED`               | `"treasury"`        | `[seed]`                                       |
| `WRAPPER_CONFIG_SEED`         | `"wrapper_config"`  | `[seed]`                                       |
| `WRAPPER_STATS_SEED`          | `"wrapper_stats"`   | `[seed]`                                       |
| `WRAPPER_RESERVE_SEED`        | `"reserve"`         | `[seed, usdc_mint.key()]`                      |
| `WRAPPER_MINT_AUTHORITY_SEED` | `"mint_authority"`  | `[seed]`                                       |
| `ADMIN_ACTION_SEED`           | `"admin_action"`    | `[seed, action_type, nonce]`                   |
| `CT_PROOF_CONTEXT_SEED`       | `"ct_proof"`        | `[seed, proof_type]`                           |

## Account Size Constants

| Constant                  | Size (bytes) | Account                                             |
| ------------------------- | ------------ | --------------------------------------------------- |
| `AGENT_POLICY_BASE_SIZE`  | 120          | AgentPolicy (base without variable fields)          |
| `SPENDING_ENTRY_SIZE`     | 16           | Each SpendingEntry (amount + timestamp)             |
| `MAX_AGENT_POLICY_SIZE`   | \~6,680      | AgentPolicy with full rolling window + Bloom filter |
| `AGENT_REGISTRY_SIZE`     | \~5,480      | AgentRegistry entry                                 |
| `ESCROW_ACCOUNT_SIZE`     | \~162        | Escrow account                                      |
| `REPUTATION_ACCOUNT_SIZE` | \~100        | Reputation account                                  |
| `WRAPPER_CONFIG_SIZE`     | 196          | WrapperConfig                                       |
| `WRAPPER_STATS_SIZE`      | 138          | WrapperStats                                        |
| `ADMIN_ACTION_SIZE`       | 84           | AdminAction                                         |

## Compute Unit Estimates

| Constant                   | CU       | Operation                        |
| -------------------------- | -------- | -------------------------------- |
| `CU_PUBLIC_TRANSFER`       | `3,400`  | Public transfer validation       |
| `CU_CONFIDENTIAL_TRANSFER` | `50,300` | Confidential transfer validation |
| `CU_ESCROW_CREATION`       | `2,800`  | Escrow creation                  |
| `CU_POLICY_UPDATE`         | `1,500`  | Policy update                    |
| `CU_MERKLE_VERIFY`         | `2,000`  | Merkle proof verification        |
| `CU_BLOOM_VERIFY`          | `800`    | Bloom filter verification        |
| `CU_DOMAIN_VERIFY`         | `400`    | Domain prefix verification       |

## Reputation System

| Constant                          | Value  | Description                              |
| --------------------------------- | ------ | ---------------------------------------- |
| `REPUTATION_SUCCESS_WEIGHT`       | `0.60` | Weight for success rate in score formula |
| `REPUTATION_RESOLUTION_WEIGHT`    | `0.15` | Weight for dispute resolution rate       |
| `REPUTATION_DISPUTE_WEIGHT`       | `0.10` | Weight for (1 - dispute rate)            |
| `REPUTATION_FAILURE_WEIGHT`       | `0.15` | Weight for (1 - failure rate)            |
| `REPUTATION_DECAY_RATE_BPS`       | `100`  | 1% monthly decay                         |
| `MIN_TRANSACTIONS_FOR_REPUTATION` | `10`   | Minimum transactions for reliable score  |

## Registry Configuration

| Constant                         | Value         | Description                       |
| -------------------------------- | ------------- | --------------------------------- |
| `REGISTRY_LISTING_FEE_LAMPORTS`  | `100,000,000` | 0.1 SOL listing fee               |
| `MAX_ENDPOINT_LENGTH`            | `256`         | Max endpoint URL length           |
| `MAX_CAPABILITIES_PER_AGENT`     | `10`          | Max capabilities per agent        |
| `MAX_CAPABILITY_METADATA_LENGTH` | `256`         | Max metadata per capability       |
| `MAX_CAPABILITY_TYPE_LENGTH`     | `64`          | Max capability type string length |
| `REGISTRY_TTL_SECONDS`           | `300`         | 5-minute cache TTL                |

## Wrapper Configuration

| Constant                     | Value               | Description               |
| ---------------------------- | ------------------- | ------------------------- |
| `WRAPPER_REDEMPTION_FEE_BPS` | `80`                | 0.8% redemption fee       |
| `MIN_WRAPPER_FEE_BPS`        | `10`                | 0.1% minimum fee          |
| `MAX_WRAPPER_FEE_BPS`        | `500`               | 5% maximum fee            |
| `MAX_REDEMPTION_PER_TX`      | `100,000,000,000`   | 100K USDC per transaction |
| `MAX_DAILY_REDEMPTIONS`      | `1,000,000,000,000` | 1M USDC daily             |
| `MIN_RESERVE_RATIO_SCALED`   | `10,000`            | 1.0x minimum ratio        |
| `RESERVE_WARNING_THRESHOLD`  | `10,100`            | 1.01x warning threshold   |
| `ADMIN_TIMELOCK_SECONDS`     | `172,800`           | 48-hour timelock          |
| `MIN_DEPOSIT_AMOUNT`         | `1,000,000`         | 1 USDC minimum deposit    |
| `MIN_REDEMPTION_AMOUNT`      | `1,000,000`         | 1 USDC minimum redemption |
| `WRAPPER_DECIMALS`           | `6`                 | Must match USDC decimals  |

## Confidential Transfer Configuration

| Constant                              | Value      | Description                                      |
| ------------------------------------- | ---------- | ------------------------------------------------ |
| `ELGAMAL_PUBKEY_SIZE`                 | `32`       | Compressed Ristretto point                       |
| `DECRYPTABLE_BALANCE_SIZE`            | `36`       | AES-encrypted decryptable balance                |
| `ELGAMAL_CIPHERTEXT_SIZE`             | `64`       | Two compressed Ristretto points                  |
| `MAX_CONFIDENTIAL_AMOUNT`             | `2^48 - 1` | Token-2022 ZK proof limit                        |
| `MAX_PENDING_BALANCE_CREDIT_COUNTER`  | `65,536`   | Max incoming transfers before apply              |
| `PUBKEY_VALIDITY_PROOF_SIZE`          | `64`       | PubkeyValidityProof data                         |
| `ZERO_CIPHERTEXT_PROOF_SIZE`          | `96`       | ZeroCiphertextProof data                         |
| `WITHDRAW_PROOF_SIZE`                 | `160`      | WithdrawProof data                               |
| `TRANSFER_PROOF_SIZE`                 | `288`      | TransferProof data (ciphertext validity + range) |
| `CONFIDENTIAL_ACCOUNT_EXTENSION_SIZE` | `~120`     | Account extension additional space               |