> For the complete documentation index, see [llms.txt](https://docs.coti.io/coti-documentation/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.coti.io/coti-documentation/privacy-on-demand/glossary.md). # Glossary Short definitions for **Privacy on Demand** readers. Precise Solidity definitions and type tables are in the [PoD SDK contract types](https://github.com/coti-io/coti-sdk-pod/tree/main/site/contracts/01-it-ct-gt-data-types) document. | Term | Meaning | | ------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **Privacy on Demand (PoD)** | Pattern and tooling for **private computation on COTI** while **orchestrating** from **another EVM chain** via an **Inbox**. | | **Inbox** | On-chain **message router** on each chain that forwards private jobs toward COTI and delivers callbacks. Implementation in [`coti-pod-inbox-contracts`](https://github.com/coti-io/coti-pod-inbox-contracts). | | **MPC executor** | COTI-side contract configured as the execution target for **library-style** PoD flows; referenced from your dApp’s routing configuration. | | **PodUser** | Solidity **configuration mixin** for Inbox address, COTI chain id, and executor address; changes should be **governed** (for example `onlyOwner`). | | **PodUserSepolia / PodUserFuji** | Network presets that auto-wire inbox and COTI routing in the constructor. | | **PodLib** | Solidity **helper library** for built-in private operations at 64/128/256-bit widths. | | **`it*` (input types)** | Encrypted user input with signature material, prepared client-side and sent to your contract. | | **`gt*` (garbled / compute types)** | Internal private representation during computation on **COTI**—not something your EVM contract should expose as a public API. | | **`ct*` (ciphertext types)** | Encrypted outputs suitable to store on your chain; users decrypt locally with the account AES key. | | **PoA / PoD fees** | Native token on your chain funding COTI-side and callback execution budgets for **two-way Inbox** traffic. See [How do PoA fees work?](/coti-documentation/privacy-on-demand/how-poa-fees-work.md). | | **Two-way message** | Outbound request to COTI plus inbound callback to your contract; typically needs fee planning for both legs. | | **Request ID** | 32-byte correlator tying submission to callback; indexed in compact `MessageSent` events. Essential for async UX and troubleshooting. | | **System error** | Pre-execution Inbox failure (encode / `validateCiphertext`). Delivered on the same `errorSelector(bytes)` as app `raise`. Attributed to `SYSTEM_SENDER`. Detect via `inboxErrorType() == SystemError`. **Not** eligible for `retryFailedRequest`. | | **`SYSTEM_SENDER`** | Placeholder `originalSender` / `inboxMsgSender()` for system-error return legs. Not a real contract; do not require it to equal your COTI peer. | | **`inboxErrorType()`** | Inbox view returning `NotErrorContext`, `SystemError`, or `Exception` for the active execution — preferred way for error handlers to branch. | | **Execution failure (code `1`)** | Target ran and reverted without `raise`. Stored on COTI with capped returndata; **permissionless** `retryFailedRequest` while code remains `1`. | | **`getOutboxError`** | View that returns `(code, data)` — for execution failures, the **raw capped returndata** (≤256 bytes). Decode in the client. | | **`executed` / `IncomingResponseReceived`** | Mean the **return or error leg was ingested** by the Inbox—not that the application callback committed. Confirm UX success via app status / events. | | **One-way message** | Outbound-only Inbox send. **Cannot** register a non-zero `errorSelector` (use two-way if you need error callbacks). | | **`retryFailedRequest`** | Permissionless COTI Inbox call that re-executes a request still marked execution-failed (code `1`). Encode failure on retry **reverts** and preserves code `1`. | | **Gas-price bounds** | Operator-configured floor / ceiling / min priority used when converting fee wei into gas-unit budgets (bounded reference price—not raw tip manipulation). | | **Account AES key** | 32-hex-character user secret for decrypting `ct*` outputs after onboarding; must be handled like credentials. See [Account Onboard](/coti-documentation/build-on-coti/guides/account-onboard.md). | | **PodRequest** | TypeScript helper (`@coti/pod-sdk`) that polls inbox state across chains for async UX. | | **PodSdkConfig** | JSON config (chains, inbox addresses, RPCs, encryption network) shared by `PodContract` and `PodRequest`. | | **`@coti-io/coti-contracts`** | npm package with PoD Solidity libraries, interfaces, and examples. | | **`@coti-io/coti-pod-inbox-contracts`** | npm package with Inbox implementation, fee manager, and miner contracts. | --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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