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

# Glossary

| Term                      | Meaning                                                                                                                                     |
| ------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------- |
| **Feed**                  | Application-facing data source backed by a deterministic `feedId` and signed payloads. It may also have a maintained Solana `Feed` account. |
| **Solana `Feed` account** | Account holding the latest verified value for a feed; PDA `["molpha_feed", feed_id]`.                                                       |
| **Round**                 | One coordination event: one fetch, one signing session, one aggregate signature.                                                            |
| **DataUpdate**            | The self-contained signed result payload: feedId, registryVersion, signaturesRequired, value, canonicalTimestamp.                           |
| **Canonical timestamp**   | The round timestamp included in the signed message; the basis for staleness checks.                                                         |
| **Registry version**      | An immutable snapshot of the node-key set; incremented on every add/remove.                                                                 |
| **Selection set**         | The pseudo-random subset of nodes eligible to sign a given round, derived from `(feedId, registryVersion, canonicalTimestamp)`.             |
| **Group size**            | `signaturesRequired + redundancyBuffer`, capped at `nodeCount`; the size of the selection set.                                              |
| **Redundancy buffer**     | Admin parameter widening the selection set beyond the threshold so dropouts don't fail the round.                                           |
| **Signers bitmap**        | A 256-bit word where bit `i-1` marks 1-based node index `i` as a signer; bound into the signed message.                                     |
| **Coalition key**         | Plain EC sum of the signers' public keys; the effective public key for the aggregate signature.                                             |
| **Commitment**            | Ethereum-style address (low 160 bits) of the Schnorr nonce point `R`.                                                                       |
| **PoP**                   | Proof-of-Possession; a Schnorr signature proving control of a node key at registration. Molpha's sole rogue-key defense.                    |
| **Plan / Subscription**   | USDC tier definition / a consumer's active monthly subscription on Solana; required to maintain feeds, not to read feeds.                   |
| **Delegate**              | Hot agent authority under a subscription (`["molpha_delegate", owner, delegate]`) with request and quorum caps.                             |
| **x402 escrow**           | Pay-per-request agent path: HTTP `402` funding loop plus on-chain `AgentEscrow` ATA settled by `settle_agent_round`.                        |
| **AgentEscrow**           | Solana PDA + USDC ATA for x402 agent rounds (`["molpha_agent", authority, gateway]`). Not a separate access model from x402.                |
| **Gateway**               | HTTP service that dispatches signing rounds, returns payloads, and handles agent payment/settlement routing.                                |