diff --git a/docs/API_DESIGN.md b/docs/API_DESIGN.md
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+# tbDEX API Design (APID) <!-- omit in toc -->
+
+**Last Updated:** June 13, 2024
+
+**Custom DSL Version:** 0.1.0
+
+- [Web5 Dependencies](#web5-dependencies)
+- [Resources](#resources)
+  - [`ResourceKind`](#resourcekind)
+  - [`ResourceMetadata`](#resourcemetadata)
+  - [`Offering`](#offering)
+    - [`OfferingData`](#offeringdata)
+    - [`PayinDetails`](#payindetails)
+    - [`PayinMethod`](#payinmethod)
+    - [`PayoutDetails`](#payoutdetails)
+    - [`PayoutMethod`](#payoutmethod)
+  - [`Balance`](#balance)
+    - [`BalanceData`](#balancedata)
+- [Messages](#messages)
+  - [`MessageKind`](#messagekind)
+  - [`MessageMetadata`](#messagemetadata)
+  - [`Rfq`](#rfq)
+    - [`CreateRfqData`](#createrfqdata)
+    - [`CreateSelectedPayinMethod`](#createselectedpayinmethod)
+    - [`CreateSelectedPayoutMethod`](#createselectedpayoutmethod)
+    - [`RfqData`](#rfqdata)
+    - [`SelectedPayinMethod`](#selectedpayinmethod)
+    - [`SelectedPayoutMethod`](#selectedpayoutmethod)
+    - [`RfqPrivateData`](#rfqprivatedata)
+    - [`PrivatePaymentDetails`](#privatepaymentdetails)
+  - [`Quote`](#quote)
+    - [`QuoteData`](#quotedata)
+    - [`QuoteDetails`](#quotedetails)
+    - [`PaymentInstructions`](#paymentinstructions)
+  - [`Order`](#order)
+  - [`OrderStatus`](#orderstatus)
+    - [`OrderStatusData`](#orderstatusdata)
+  - [`Close`](#close)
+    - [`CloseData`](#closedata)
+- [HTTP Client](#http-client)
+  - [`Exchange`](#exchange)
+  - [`get_offerings()`](#get_offerings)
+  - [`get_balances()`](#get_balances)
+  - [`create_exchange()`](#create_exchange)
+  - [`submit_order()`](#submit_order)
+  - [`submit_close()`](#submit_close)
+  - [`get_exchange()`](#get_exchange)
+  - [`get_exchanges()`](#get_exchanges)
+
+> [!WARNING]
+>
+> We need to define `JsonNode`
+
+> [!WARNING]
+>
+> Snake vs camel casing is inconsistent
+
+> [!WARNING]
+>
+> `FUNCTION` needs to be added to the Custom DSL
+
+# Web5 Dependencies
+
+- `PresentationDefinition`
+- `BearerDid`
+
+> [!WARNING]
+>
+> 🚧 Add links to Web5 APID
+
+# Resources
+
+## `ResourceKind`
+
+```pseudocode!
+ENUM ResourceKind
+  offering,
+  balance,
+```
+
+## `ResourceMetadata`
+
+```pseudocode!
+CLASS ResourceMetadata
+  PUBLIC DATA kind: string
+  PUBLIC DATA from: string
+  PUBLIC DATA to: string
+  PUBLIC DATA id: string
+  PUBLIC DATA protocol: string
+  PUBLIC DATA createdAt: string
+  PUBLIC DATA updatedAt: string?
+```
+
+## `Offering`
+
+> [!NOTE]
+>
+> All `CONSTRUCTOR(json: string)` instances in this APID perform cryptographic verification on the `signature` property.
+
+```pseudocode!
+CLASS Offering IMPLEMENTS Resource
+  PUBLIC DATA metadata: ResourceMetadata
+  PUBLIC DATA data: OfferingData
+  PUBLIC DATA signature: string
+  CONSTRUCTOR(bearer_did: BearerDid, from: string, data: OfferingData, protocol: string)
+  CONSTRUCTOR(json: string) 
+  METHOD to_json(): string
+```
+
+### `OfferingData`
+
+```pseudocode!
+CLASS OfferingData
+  PUBLIC DATA description: string
+  PUBLIC DATA payoutUnitsPerPayinUnit: string
+  PUBLIC DATA payin PayinDetails
+  PUBLIC DATA payout PayoutDetails
+  PUBLIC DATA requiredClaims PresentationDefinition
+```
+
+### `PayinDetails`
+
+```pseudocode!
+CLASS PayinDetails
+  PUBLIC DATA currencyCode: string
+  PUBLIC DATA min: string?
+  PUBLIC DATA max: string?
+  PUBLIC DATA methods: []PayinMethod
+```
+
+### `PayinMethod`
+
+```pseudocode!
+CLASS PayinMethod
+  PUBLIC DATA kind: string
+  PUBLIC DATA name: string?
+  PUBLIC DATA description: string?
+  PUBLIC DATA group: string?
+  PUBLIC DATA requiredPaymentDetails: JsonNode? // 🚧
+  PUBLIC DATA fee: string?
+  PUBLIC DATA min: string?
+  PUBLIC DATA max: string?
+```
+
+### `PayoutDetails`
+
+```pseudocode!
+CLASS PayoutDetails
+  PUBLIC DATA currencyCode: string
+  PUBLIC DATA min: string?
+  PUBLIC DATA max: string?
+  PUBLIC DATA methods: []PayoutMethod
+```
+
+### `PayoutMethod`
+
+```pseudocode!
+CLASS PayinMethod
+  PUBLIC DATA kind: string
+  PUBLIC DATA name: string?
+  PUBLIC DATA description: string?
+  PUBLIC DATA group: string?
+  PUBLIC DATA requiredPaymentDetails: JsonNode? // 🚧
+  PUBLIC DATA fee: string?
+  PUBLIC DATA min: string?
+  PUBLIC DATA max: string?
+  PUBLIC DATA estimatedSettlementTime: int
+```
+
+## `Balance`
+
+```pseudocode!
+CLASS Balance IMPLEMENTS Resource
+  PUBLIC DATA metadata: ResourceMetadata
+  PUBLIC DATA data: BalanceData
+  PUBLIC DATA signature: string
+  CONSTRUCTOR(bearer_did: BearerDid, from: string, data: BalanceData, protocol: string)
+  CONSTRUCTOR(json: string)
+  METHOD to_json(): string
+```
+
+### `BalanceData`
+
+```pseudocode!
+CLASS BalanceData
+  PUBLIC DATA currencyCode: string
+  PUBLIC DATA available: string
+```
+
+# Messages
+
+## `MessageKind`
+
+```pseudocode!
+ENUM MessageKind
+  rfq,
+  quote,
+  order,
+  orderstatus,
+  close,
+```
+
+## `MessageMetadata`
+
+```pseudocode!
+CLASS MessageMetadata
+  PUBLIC DATA from: string
+  PUBLIC DATA to: string
+  PUBLIC DATA kind: MessageKind
+  PUBLIC DATA id: string
+  PUBLIC DATA exchangeId: string
+  PUBLIC DATA externalId: string?
+  PUBLIC DATA createdAt: string
+  PUBLIC DATA protocol: string
+```
+
+## `Rfq`
+
+```pseudocode!
+CLASS Rfq IMPLEMENTS Message
+  PUBLIC DATA metadata: MessageMetadata
+  PUBLIC DATA data: RfqData
+  PUBLIC DATA privateData: RfqPrivateData
+  PUBLIC DATA signature: string
+  CONSTRUCTOR(bearer_did: BearerDid, to: string, from: string, rfqData: CreateRfqData, protocol: string, externalId: string?)
+  CONSTRUCTOR(json: string, requireAllPrivateData: bool?)
+  METHOD to_json(): string
+```
+
+### `CreateRfqData`
+
+```pseudocode!
+CLASS CreateRfqData
+  PUBLIC DATA offeringId: string
+  PUBLIC DATA payin: CreateSelectedPayinMethod
+  PUBLIC DATA payout: CreateSelectedPayoutMethod
+  PUBLIC DATA claims: []string
+```
+
+### `CreateSelectedPayinMethod`
+
+```pseudocode!
+CLASS CreateSelectedPayinMethod
+  PUBLIC DATA kind: string
+  PUBLIC DATA paymentDetails: Map<string, JsonNode>? // 🚧
+  PUBLIC DATA amount: string
+```
+
+### `CreateSelectedPayoutMethod`
+
+```pseudocode!
+CLASS CreateSelectedPayoutMethod
+  PUBLIC DATA kind: string
+  PUBLIC DATA paymentDetails: Map<string, JsonNode> // 🚧
+```
+
+### `RfqData`
+
+```pseudocode!
+CLASS RfqData
+  PUBLIC DATA offeringId: string
+  PUBLIC DATA payin: SelectedPayinMethod
+  PUBLIC DATA payout: SelectedPayoutMethod
+  PUBLIC DATA claimsHash: string?
+```
+
+### `SelectedPayinMethod`
+
+```pseudocode!
+CLASS SelectedPayinMethod
+  PUBLIC DATA kind: string
+  PUBLIC DATA paymentDetailsHash: string?
+  PUBLIC DATA amount: string
+```
+
+### `SelectedPayoutMethod`
+
+```pseudocode!
+CLASS SelectedPayoutMethod
+  PUBLIC DATA kind: string
+  PUBLIC DATA paymentDetailsHash: string?
+```
+
+### `RfqPrivateData`
+
+```pseudocode!
+CLASS RfqPrivateData
+  PUBLIC DATA salt: string
+  PUBLIC DATA payin: PrivatePaymentDetails?
+  PUBLIC DATA payout: PrivatePaymentDetails?
+  PUBLIC DATA claims: []string?
+```
+
+### `PrivatePaymentDetails`
+
+```pseudocode!
+CLASS PrivatePaymentDetails
+  PUBLIC DATA paymentDetails: Map<string, JsonNode>? // 🚧
+```
+
+## `Quote`
+
+```pseudocode!
+CLASS Quote IMPLEMENTS Message
+  PUBLIC DATA metadata: MessageMetadata
+  PUBLIC DATA data: QuoteData
+  PUBLIC DATA signature: string
+  CONSTRUCTOR(bearer_did: BearerDid, to: string, from: string, exchangeId: string, quoteData: QuoteData, protocol: string, externalId: string?)
+  CONSTRUCTOR(json: string)
+  METHOD to_json(): string
+```
+
+### `QuoteData`
+
+```pseudocode!
+CLASS QuoteData
+  PUBLIC DATA expiresAt: string
+  PUBLIC DATA payin: QuoteDetails
+  PUBLIC DATA payout: QuoteDetails
+```
+
+### `QuoteDetails`
+
+```pseudocode!
+CLASS QuoteDetails
+  PUBLIC DATA currencyCode: string
+  PUBLIC DATA amount: string
+  PUBLIC DATA fee: string?
+  PUBLIC DATA paymentInstructions: PaymentInstructions?
+```
+
+### `PaymentInstructions`
+
+```pseudocode!
+CLASS PaymentInstructions
+  PUBLIC DATA link: string?
+  PUBLIC DATA instruction: string?
+```
+
+## `Order`
+
+```pseudocode!
+CLASS Order IMPLEMENTS Message
+  PUBLIC DATA metadata: MessageMetadata
+  PUBLIC DATA signature: string
+  CONSTRUCTOR(bearer_did: BearerDid, to: string, from: string, exchangeId: string, protocol: string, externalId: string?)
+  CONSTRUCTOR(json: string)
+  METHOD to_json(): string
+```
+
+## `OrderStatus`
+
+```pseudocode!
+CLASS OrderStatus IMPLEMENTS Message
+  PUBLIC DATA metadata: MessageMetadata
+  PUBLIC DATA data: OrderStatusData
+  PUBLIC DATA signature: string
+  CONSTRUCTOR(bearer_did: BearerDid, to: string, from: string, exchangeId: string, orderStatusData: OrderStatusData, protocol: string, externalId: string?)
+  CONSTRUCTOR(json: string)
+  METHOD to_json(): string
+```
+
+### `OrderStatusData`
+
+```pseudocode!
+CLASS OrderStatusData
+  PUBLIC DATA orderStatus: string
+```
+
+## `Close`
+
+```pseudocode!
+CLASS Close IMPLEMENTS Message
+  PUBLIC DATA metadata: MessageMetadata
+  PUBLIC DATA data: CloseData
+  PUBLIC DATA signature: string
+  CONSTRUCTOR(bearer_did: BearerDid, to: string, from: string, exchangeId: string, closeData: CloseData, protocol: string, externalId: string?)
+  CONSTRUCTOR(json: string)
+  METHOD to_json(): string
+```
+
+### `CloseData`
+
+```pseudocode!
+CLASS CloseData
+  PUBLIC DATA reason: string?
+  PUBLIC DATA success: bool?
+```
+
+# HTTP Client
+
+## `Exchange`
+
+```pseudocode!
+CLASS Exchange
+  PUBLIC DATA rfq: Rfq
+  PUBLIC DATA quote: Quote
+  PUBLIC DATA order: Order
+  PUBLIC DATA order_statuses: []OrderStatus
+  PUBLIC DATA close: Close
+```
+
+## `get_offerings()`
+
+```pseudocode!
+FUNCTION get_offerings(pfi_did_uri: string): []Offering
+```
+
+## `get_balances()`
+
+```pseudocode!
+FUNCTION get_balances(pfi_did_uri: string, bearer_did: BearerDid): []Balance
+```
+
+## `create_exchange()`
+
+```pseudocode!
+FUNCTION create_exchange(rfq: Rfq, reply_to: string?)
+```
+
+## `submit_order()`
+
+```pseudocode!
+FUNCTION submit_order(order: Order)
+```
+
+## `submit_close()`
+
+```pseudocode!
+FUNCTION submit_close(order: Order)
+```
+
+## `get_exchange()`
+
+```pseudocode!
+FUNCTION get_exchange(pfi_did_uri: string, bearer_did: BearerDid, exchange_id: string): Exchange
+```
+
+## `get_exchanges()`
+
+```pseudocode!
+FUNCTION get_exchanges(pfi_did_uri: string, bearer_did: BearerDid): []string
+```
diff --git a/docs/rfcs/rfc-0001/README.md b/docs/rfcs/rfc-0001/README.md
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+# RFC-0001 Standard tbDEX API Design (APID) Document v0.1.0 <!-- omit in toc -->
+
+- [Summary](#summary)
+- [Motivation](#motivation)
+- [Detailed Design](#detailed-design)
+  - [Known Limitations](#known-limitations)
+- [Drawbacks](#drawbacks)
+- [Alternatives](#alternatives)
+- [Prior Art](#prior-art)
+
+# Summary
+
+Lay the initial foundations to drive early implementations, with the expectation to subsequently iterate and build upon.
+
+# Motivation
+
+The driving motivations for a standard API design, adopted across many language implementations, is well defined in the [Web5 RFC-0001](https://github.com/TBD54566975/web5-rs/blob/main/docs/rfcs/rcf-0001/README.md#motivation).
+
+# Detailed Design
+
+This RFC defines version 0.1.0 of the APID, but is expected to change hereafter. 
+
+Many of the design decisions were made from prior implementations, namely [the `tbdex-kt` implementation](https://github.com/TBD54566975/tbdex-kt/). Primary deviations from the [pre-existing `tbdex-kt` implementation](https://github.com/TBD54566975/tbdex-kt/) are three-fold.
+
+1. A difference of namespacing. Although namespacing is not currently explicitly supported in the [Custom DSL](https://github.com/TBD54566975/web5-rs/blob/main/docs/CUSTOM_DSL.md), the hierarchy of the APID markdown file has implicit intentions of namespacing.
+2. Migration away from a class `TbdexHttpClient` with static methods, wherein the class served no purpose other than an obscure namespace, and towards functions -- for example, instead of `TbdexHttpClient.getOfferings()` it's now `tbdex.httpclient` (namespaces) and a function `getOfferings()`.
+3. No polymorphic base classes for `Resource` and `Message`. Polymorphism is primarily relevant for use cases of developer-defined instances, for example a "bring-your-own" cryptography abstraction wherein the SDK cannot support the full enumeration of possible use cases, but that's not the case for tbDEX resources and messages, both of which are well-defined. For situations of DRY, permissions are encouraged.
+
+## Known Limitations
+
+- Lack of support for `FUNCTIONS` in the [Custom DSL](https://github.com/TBD54566975/web5-rs/blob/main/docs/CUSTOM_DSL.md).
+- Lack of support for a JSON Object type in the [Custom DSL](https://github.com/TBD54566975/web5-rs/blob/main/docs/CUSTOM_DSL.md).
+- Snake casing and camel casing is inconsistent.
+- No "HTTP Server" functionality.
+
+# Drawbacks
+
+None.
+
+# Alternatives
+
+None.
+
+# Prior Art
+
+Heavily inspired by [Web5 RFC-0001](https://github.com/TBD54566975/web5-rs/blob/main/docs/rfcs/rcf-0001/README.md).
\ No newline at end of file