diff --git a/.release-please-manifest.json b/.release-please-manifest.json
index c412e9745..52b3e8341 100644
--- a/.release-please-manifest.json
+++ b/.release-please-manifest.json
@@ -1,3 +1,3 @@
 {
-  ".": "0.1.0-alpha.29"
+  ".": "0.1.0-alpha.30"
 }
\ No newline at end of file
diff --git a/.stats.yml b/.stats.yml
index f57d811d6..43c250262 100644
--- a/.stats.yml
+++ b/.stats.yml
@@ -1,4 +1,4 @@
-configured_endpoints: 196
-openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/increase%2Fincrease-18c5248f747fed10c6251e99ce19ff8baf99aba8a660b97f3b2f0c956c3b68eb.yml
-openapi_spec_hash: fee11521b46e6468507255ffead78f8e
-config_hash: c4ca49f6bac6268578b0734a33a9d1fd
+configured_endpoints: 197
+openapi_spec_url: https://storage.googleapis.com/stainless-sdk-openapi-specs/increase%2Fincrease-b9a610bb578b82c46d4222f4746d69c8e422f9cfad51a6d72d44c64f8746d709.yml
+openapi_spec_hash: a63cc36300445b0201442108b6cc8530
+config_hash: 85850cd9055db4b9e43bcc4aa1a2dcea
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5b0c3bd91..be1eb40ee 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,21 @@
 # Changelog
 
+## 0.1.0-alpha.30 (2025-06-03)
+
+Full Changelog: [v0.1.0-alpha.29...v0.1.0-alpha.30](https://github.com/Increase/increase-ruby/compare/v0.1.0-alpha.29...v0.1.0-alpha.30)
+
+### Features
+
+* **api:** api update ([bb7f9d3](https://github.com/Increase/increase-ruby/commit/bb7f9d31c20555ba9391376680a6efdbb667e81d))
+* **api:** api update ([6211a95](https://github.com/Increase/increase-ruby/commit/6211a959e8612d7974fcdbc0076f068bc1a90025))
+* **api:** api update ([39d9b4c](https://github.com/Increase/increase-ruby/commit/39d9b4c8731658a5568bb974cd9334f07c83bb4f))
+* **api:** api update ([4f9aad6](https://github.com/Increase/increase-ruby/commit/4f9aad6968a09f1549b32d98d19dddced537403f))
+
+
+### Bug Fixes
+
+* `to_sorbet_type` should not return branded types ([4dd5dff](https://github.com/Increase/increase-ruby/commit/4dd5dffdb9d333152cb5d759c763f4b0cfd15afd))
+
 ## 0.1.0-alpha.29 (2025-05-28)
 
 Full Changelog: [v0.1.0-alpha.28...v0.1.0-alpha.29](https://github.com/Increase/increase-ruby/compare/v0.1.0-alpha.28...v0.1.0-alpha.29)
diff --git a/Gemfile.lock b/Gemfile.lock
index 665b4365a..b5d9da092 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -11,7 +11,7 @@ GIT
 PATH
   remote: .
   specs:
-    increase (0.1.0.pre.alpha.29)
+    increase (0.1.0.pre.alpha.30)
       connection_pool
 
 GEM
diff --git a/README.md b/README.md
index 7e5ca5606..d3963193c 100644
--- a/README.md
+++ b/README.md
@@ -15,7 +15,7 @@ To use this gem, install via Bundler by adding the following to your application
 <!-- x-release-please-start-version -->
 
 ```ruby
-gem "increase", "~> 0.1.0.pre.alpha.29"
+gem "increase", "~> 0.1.0.pre.alpha.30"
 ```
 
 <!-- x-release-please-end -->
diff --git a/lib/increase.rb b/lib/increase.rb
index ebb9b0236..c4da7e2ae 100644
--- a/lib/increase.rb
+++ b/lib/increase.rb
@@ -137,6 +137,7 @@
 require_relative "increase/models/digital_wallet_token_list_params"
 require_relative "increase/models/digital_wallet_token_retrieve_params"
 require_relative "increase/models/document"
+require_relative "increase/models/document_create_params"
 require_relative "increase/models/document_list_params"
 require_relative "increase/models/document_retrieve_params"
 require_relative "increase/models/entity"
diff --git a/lib/increase/internal/type/enum.rb b/lib/increase/internal/type/enum.rb
index 962152e7c..073351bd6 100644
--- a/lib/increase/internal/type/enum.rb
+++ b/lib/increase/internal/type/enum.rb
@@ -91,11 +91,14 @@ def coerce(value, state:)
         #
         # @return [Object]
         def to_sorbet_type
-          case values
+          types = values.map { Increase::Internal::Util::SorbetRuntimeSupport.to_sorbet_type(_1) }.uniq
+          case types
           in []
             T.noreturn
-          in [value, *_]
-            T.all(Increase::Internal::Util::SorbetRuntimeSupport.to_sorbet_type(value), self)
+          in [type]
+            type
+          else
+            T.any(*types)
           end
         end
 
diff --git a/lib/increase/internal/type/union.rb b/lib/increase/internal/type/union.rb
index 0e9dddf7c..27475fecf 100644
--- a/lib/increase/internal/type/union.rb
+++ b/lib/increase/internal/type/union.rb
@@ -195,11 +195,14 @@ def dump(value, state:)
         #
         # @return [Object]
         def to_sorbet_type
-          case (v = variants)
+          types = variants.map { Increase::Internal::Util::SorbetRuntimeSupport.to_sorbet_type(_1) }.uniq
+          case types
           in []
             T.noreturn
+          in [type]
+            type
           else
-            T.any(*v.map { Increase::Internal::Util::SorbetRuntimeSupport.to_sorbet_type(_1) })
+            T.any(*types)
           end
         end
 
diff --git a/lib/increase/models.rb b/lib/increase/models.rb
index 32c1b8828..63ac94ea1 100644
--- a/lib/increase/models.rb
+++ b/lib/increase/models.rb
@@ -11,16 +11,16 @@ module Increase
       mod.constants.each do |name|
         case mod.const_get(name)
         in true | false
-          mod.define_sorbet_constant!(:TaggedBoolean) { T.type_alias { T.all(T::Boolean, mod) } }
+          mod.define_sorbet_constant!(:TaggedBoolean) { T.type_alias { T::Boolean } }
           mod.define_sorbet_constant!(:OrBoolean) { T.type_alias { T::Boolean } }
         in Integer
-          mod.define_sorbet_constant!(:TaggedInteger) { T.type_alias { T.all(Integer, mod) } }
+          mod.define_sorbet_constant!(:TaggedInteger) { T.type_alias { Integer } }
           mod.define_sorbet_constant!(:OrInteger) { T.type_alias { Integer } }
         in Float
-          mod.define_sorbet_constant!(:TaggedFloat) { T.type_alias { T.all(Float, mod) } }
+          mod.define_sorbet_constant!(:TaggedFloat) { T.type_alias { Float } }
           mod.define_sorbet_constant!(:OrFloat) { T.type_alias { Float } }
         in Symbol
-          mod.define_sorbet_constant!(:TaggedSymbol) { T.type_alias { T.all(Symbol, mod) } }
+          mod.define_sorbet_constant!(:TaggedSymbol) { T.type_alias { Symbol } }
           mod.define_sorbet_constant!(:OrSymbol) { T.type_alias { T.any(Symbol, String) } }
         else
         end
@@ -211,6 +211,8 @@ module Increase
 
   Document = Increase::Models::Document
 
+  DocumentCreateParams = Increase::Models::DocumentCreateParams
+
   DocumentListParams = Increase::Models::DocumentListParams
 
   DocumentRetrieveParams = Increase::Models::DocumentRetrieveParams
diff --git a/lib/increase/models/document.rb b/lib/increase/models/document.rb
index 24fb30536..303e7f01c 100644
--- a/lib/increase/models/document.rb
+++ b/lib/increase/models/document.rb
@@ -2,7 +2,7 @@
 
 module Increase
   module Models
-    # @see Increase::Resources::Documents#retrieve
+    # @see Increase::Resources::Documents#create
     class Document < Increase::Internal::Type::BaseModel
       # @!attribute id
       #   The Document identifier.
@@ -10,6 +10,12 @@ class Document < Increase::Internal::Type::BaseModel
       #   @return [String]
       required :id, String
 
+      # @!attribute account_verification_letter
+      #   Properties of an account verification letter document.
+      #
+      #   @return [Increase::Models::Document::AccountVerificationLetter, nil]
+      required :account_verification_letter, -> { Increase::Document::AccountVerificationLetter }, nil?: true
+
       # @!attribute category
       #   The type of document.
       #
@@ -35,6 +41,14 @@ class Document < Increase::Internal::Type::BaseModel
       #   @return [String]
       required :file_id, String
 
+      # @!attribute idempotency_key
+      #   The idempotency key you chose for this object. This value is unique across
+      #   Increase and is used to ensure that a request is only processed once. Learn more
+      #   about [idempotency](https://increase.com/documentation/idempotency-keys).
+      #
+      #   @return [String, nil]
+      required :idempotency_key, String, nil?: true
+
       # @!attribute type
       #   A constant representing the object's type. For this resource it will always be
       #   `document`.
@@ -42,7 +56,7 @@ class Document < Increase::Internal::Type::BaseModel
       #   @return [Symbol, Increase::Models::Document::Type]
       required :type, enum: -> { Increase::Document::Type }
 
-      # @!method initialize(id:, category:, created_at:, entity_id:, file_id:, type:)
+      # @!method initialize(id:, account_verification_letter:, category:, created_at:, entity_id:, file_id:, idempotency_key:, type:)
       #   Some parameter documentations has been truncated, see
       #   {Increase::Models::Document} for more details.
       #
@@ -51,6 +65,8 @@ class Document < Increase::Internal::Type::BaseModel
       #
       #   @param id [String] The Document identifier.
       #
+      #   @param account_verification_letter [Increase::Models::Document::AccountVerificationLetter, nil] Properties of an account verification letter document.
+      #
       #   @param category [Symbol, Increase::Models::Document::Category] The type of document.
       #
       #   @param created_at [Time] The [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601) time at which the Documen
@@ -59,8 +75,24 @@ class Document < Increase::Internal::Type::BaseModel
       #
       #   @param file_id [String] The identifier of the File containing the Document's contents.
       #
+      #   @param idempotency_key [String, nil] The idempotency key you chose for this object. This value is unique across Incre
+      #
       #   @param type [Symbol, Increase::Models::Document::Type] A constant representing the object's type. For this resource it will always be `
 
+      # @see Increase::Models::Document#account_verification_letter
+      class AccountVerificationLetter < Increase::Internal::Type::BaseModel
+        # @!attribute account_number_id
+        #   The identifier of the Account Number the document was generated for.
+        #
+        #   @return [String]
+        required :account_number_id, String
+
+        # @!method initialize(account_number_id:)
+        #   Properties of an account verification letter document.
+        #
+        #   @param account_number_id [String] The identifier of the Account Number the document was generated for.
+      end
+
       # The type of document.
       #
       # @see Increase::Models::Document#category
@@ -79,6 +111,9 @@ module Category
         # Company information, such a policies or procedures, typically submitted during our due diligence process.
         COMPANY_INFORMATION = :company_information
 
+        # An account verification letter.
+        ACCOUNT_VERIFICATION_LETTER = :account_verification_letter
+
         # @!method self.values
         #   @return [Array<Symbol>]
       end
diff --git a/lib/increase/models/document_create_params.rb b/lib/increase/models/document_create_params.rb
new file mode 100644
index 000000000..29bc22bb5
--- /dev/null
+++ b/lib/increase/models/document_create_params.rb
@@ -0,0 +1,62 @@
+# frozen_string_literal: true
+
+module Increase
+  module Models
+    # @see Increase::Resources::Documents#create
+    class DocumentCreateParams < Increase::Internal::Type::BaseModel
+      extend Increase::Internal::Type::RequestParameters::Converter
+      include Increase::Internal::Type::RequestParameters
+
+      # @!attribute category
+      #   The type of document to create.
+      #
+      #   @return [Symbol, Increase::Models::DocumentCreateParams::Category]
+      required :category, enum: -> { Increase::DocumentCreateParams::Category }
+
+      # @!attribute account_verification_letter
+      #   An account verification letter.
+      #
+      #   @return [Increase::Models::DocumentCreateParams::AccountVerificationLetter, nil]
+      optional :account_verification_letter, -> { Increase::DocumentCreateParams::AccountVerificationLetter }
+
+      # @!method initialize(category:, account_verification_letter: nil, request_options: {})
+      #   @param category [Symbol, Increase::Models::DocumentCreateParams::Category] The type of document to create.
+      #
+      #   @param account_verification_letter [Increase::Models::DocumentCreateParams::AccountVerificationLetter] An account verification letter.
+      #
+      #   @param request_options [Increase::RequestOptions, Hash{Symbol=>Object}]
+
+      # The type of document to create.
+      module Category
+        extend Increase::Internal::Type::Enum
+
+        # An account verification letter.
+        ACCOUNT_VERIFICATION_LETTER = :account_verification_letter
+
+        # @!method self.values
+        #   @return [Array<Symbol>]
+      end
+
+      class AccountVerificationLetter < Increase::Internal::Type::BaseModel
+        # @!attribute account_number_id
+        #   The Account Number the bank letter should be generated for.
+        #
+        #   @return [String]
+        required :account_number_id, String
+
+        # @!attribute balance_date
+        #   If provided, the letter will include the Account's balance as of the date.
+        #
+        #   @return [Date, nil]
+        optional :balance_date, Date
+
+        # @!method initialize(account_number_id:, balance_date: nil)
+        #   An account verification letter.
+        #
+        #   @param account_number_id [String] The Account Number the bank letter should be generated for.
+        #
+        #   @param balance_date [Date] If provided, the letter will include the Account's balance as of the date.
+      end
+    end
+  end
+end
diff --git a/lib/increase/models/document_list_params.rb b/lib/increase/models/document_list_params.rb
index 564925220..f50cd99b8 100644
--- a/lib/increase/models/document_list_params.rb
+++ b/lib/increase/models/document_list_params.rb
@@ -29,6 +29,15 @@ class DocumentListParams < Increase::Internal::Type::BaseModel
       #   @return [String, nil]
       optional :entity_id, String
 
+      # @!attribute idempotency_key
+      #   Filter records to the one with the specified `idempotency_key` you chose for
+      #   that object. This value is unique across Increase and is used to ensure that a
+      #   request is only processed once. Learn more about
+      #   [idempotency](https://increase.com/documentation/idempotency-keys).
+      #
+      #   @return [String, nil]
+      optional :idempotency_key, String
+
       # @!attribute limit
       #   Limit the size of the list that is returned. The default (and maximum) is 100
       #   objects.
@@ -36,7 +45,7 @@ class DocumentListParams < Increase::Internal::Type::BaseModel
       #   @return [Integer, nil]
       optional :limit, Integer
 
-      # @!method initialize(category: nil, created_at: nil, cursor: nil, entity_id: nil, limit: nil, request_options: {})
+      # @!method initialize(category: nil, created_at: nil, cursor: nil, entity_id: nil, idempotency_key: nil, limit: nil, request_options: {})
       #   Some parameter documentations has been truncated, see
       #   {Increase::Models::DocumentListParams} for more details.
       #
@@ -48,6 +57,8 @@ class DocumentListParams < Increase::Internal::Type::BaseModel
       #
       #   @param entity_id [String] Filter Documents to ones belonging to the specified Entity.
       #
+      #   @param idempotency_key [String] Filter records to the one with the specified `idempotency_key` you chose for tha
+      #
       #   @param limit [Integer] Limit the size of the list that is returned. The default (and maximum) is 100 ob
       #
       #   @param request_options [Increase::RequestOptions, Hash{Symbol=>Object}]
@@ -84,6 +95,9 @@ module In
           # Company information, such a policies or procedures, typically submitted during our due diligence process.
           COMPANY_INFORMATION = :company_information
 
+          # An account verification letter.
+          ACCOUNT_VERIFICATION_LETTER = :account_verification_letter
+
           # @!method self.values
           #   @return [Array<Symbol>]
         end
diff --git a/lib/increase/models/file.rb b/lib/increase/models/file.rb
index ffabe4d72..039061bd9 100644
--- a/lib/increase/models/file.rb
+++ b/lib/increase/models/file.rb
@@ -189,6 +189,9 @@ module Purpose
         # A file containing additional evidence for a Proof of Authorization Request Submission.
         PROOF_OF_AUTHORIZATION_REQUEST_SUBMISSION = :proof_of_authorization_request_submission
 
+        # An account verification letter.
+        ACCOUNT_VERIFICATION_LETTER = :account_verification_letter
+
         # @!method self.values
         #   @return [Array<Symbol>]
       end
diff --git a/lib/increase/models/file_list_params.rb b/lib/increase/models/file_list_params.rb
index 36dfe7d63..042f9cb1a 100644
--- a/lib/increase/models/file_list_params.rb
+++ b/lib/increase/models/file_list_params.rb
@@ -191,6 +191,9 @@ module In
           # A file containing additional evidence for a Proof of Authorization Request Submission.
           PROOF_OF_AUTHORIZATION_REQUEST_SUBMISSION = :proof_of_authorization_request_submission
 
+          # An account verification letter.
+          ACCOUNT_VERIFICATION_LETTER = :account_verification_letter
+
           # @!method self.values
           #   @return [Array<Symbol>]
         end
diff --git a/lib/increase/resources/documents.rb b/lib/increase/resources/documents.rb
index 61a7a0180..2251553b9 100644
--- a/lib/increase/resources/documents.rb
+++ b/lib/increase/resources/documents.rb
@@ -3,6 +3,30 @@
 module Increase
   module Resources
     class Documents
+      # Create a Document
+      #
+      # @overload create(category:, account_verification_letter: nil, request_options: {})
+      #
+      # @param category [Symbol, Increase::Models::DocumentCreateParams::Category] The type of document to create.
+      #
+      # @param account_verification_letter [Increase::Models::DocumentCreateParams::AccountVerificationLetter] An account verification letter.
+      #
+      # @param request_options [Increase::RequestOptions, Hash{Symbol=>Object}, nil]
+      #
+      # @return [Increase::Models::Document]
+      #
+      # @see Increase::Models::DocumentCreateParams
+      def create(params)
+        parsed, options = Increase::DocumentCreateParams.dump_request(params)
+        @client.request(
+          method: :post,
+          path: "documents",
+          body: parsed,
+          model: Increase::Document,
+          options: options
+        )
+      end
+
       # Retrieve a Document
       #
       # @overload retrieve(document_id, request_options: {})
@@ -28,7 +52,7 @@ def retrieve(document_id, params = {})
       #
       # List Documents
       #
-      # @overload list(category: nil, created_at: nil, cursor: nil, entity_id: nil, limit: nil, request_options: {})
+      # @overload list(category: nil, created_at: nil, cursor: nil, entity_id: nil, idempotency_key: nil, limit: nil, request_options: {})
       #
       # @param category [Increase::Models::DocumentListParams::Category]
       #
@@ -38,6 +62,8 @@ def retrieve(document_id, params = {})
       #
       # @param entity_id [String] Filter Documents to ones belonging to the specified Entity.
       #
+      # @param idempotency_key [String] Filter records to the one with the specified `idempotency_key` you chose for tha
+      #
       # @param limit [Integer] Limit the size of the list that is returned. The default (and maximum) is 100 ob
       #
       # @param request_options [Increase::RequestOptions, Hash{Symbol=>Object}, nil]
diff --git a/lib/increase/version.rb b/lib/increase/version.rb
index d55f5443c..672b61ec1 100644
--- a/lib/increase/version.rb
+++ b/lib/increase/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module Increase
-  VERSION = "0.1.0.pre.alpha.29"
+  VERSION = "0.1.0.pre.alpha.30"
 end
diff --git a/rbi/increase/models.rbi b/rbi/increase/models.rbi
index 29b5c44ea..04b2668ee 100644
--- a/rbi/increase/models.rbi
+++ b/rbi/increase/models.rbi
@@ -194,6 +194,8 @@ module Increase
 
   Document = Increase::Models::Document
 
+  DocumentCreateParams = Increase::Models::DocumentCreateParams
+
   DocumentListParams = Increase::Models::DocumentListParams
 
   DocumentRetrieveParams = Increase::Models::DocumentRetrieveParams
diff --git a/rbi/increase/models/document.rbi b/rbi/increase/models/document.rbi
index 42d58b329..9e66132ef 100644
--- a/rbi/increase/models/document.rbi
+++ b/rbi/increase/models/document.rbi
@@ -10,6 +10,18 @@ module Increase
       sig { returns(String) }
       attr_accessor :id
 
+      # Properties of an account verification letter document.
+      sig { returns(T.nilable(Increase::Document::AccountVerificationLetter)) }
+      attr_reader :account_verification_letter
+
+      sig do
+        params(
+          account_verification_letter:
+            T.nilable(Increase::Document::AccountVerificationLetter::OrHash)
+        ).void
+      end
+      attr_writer :account_verification_letter
+
       # The type of document.
       sig { returns(Increase::Document::Category::TaggedSymbol) }
       attr_accessor :category
@@ -27,6 +39,12 @@ module Increase
       sig { returns(String) }
       attr_accessor :file_id
 
+      # The idempotency key you chose for this object. This value is unique across
+      # Increase and is used to ensure that a request is only processed once. Learn more
+      # about [idempotency](https://increase.com/documentation/idempotency-keys).
+      sig { returns(T.nilable(String)) }
+      attr_accessor :idempotency_key
+
       # A constant representing the object's type. For this resource it will always be
       # `document`.
       sig { returns(Increase::Document::Type::TaggedSymbol) }
@@ -37,16 +55,21 @@ module Increase
       sig do
         params(
           id: String,
+          account_verification_letter:
+            T.nilable(Increase::Document::AccountVerificationLetter::OrHash),
           category: Increase::Document::Category::OrSymbol,
           created_at: Time,
           entity_id: T.nilable(String),
           file_id: String,
+          idempotency_key: T.nilable(String),
           type: Increase::Document::Type::OrSymbol
         ).returns(T.attached_class)
       end
       def self.new(
         # The Document identifier.
         id:,
+        # Properties of an account verification letter document.
+        account_verification_letter:,
         # The type of document.
         category:,
         # The [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601) time at which the
@@ -56,6 +79,10 @@ module Increase
         entity_id:,
         # The identifier of the File containing the Document's contents.
         file_id:,
+        # The idempotency key you chose for this object. This value is unique across
+        # Increase and is used to ensure that a request is only processed once. Learn more
+        # about [idempotency](https://increase.com/documentation/idempotency-keys).
+        idempotency_key:,
         # A constant representing the object's type. For this resource it will always be
         # `document`.
         type:
@@ -66,10 +93,13 @@ module Increase
         override.returns(
           {
             id: String,
+            account_verification_letter:
+              T.nilable(Increase::Document::AccountVerificationLetter),
             category: Increase::Document::Category::TaggedSymbol,
             created_at: Time,
             entity_id: T.nilable(String),
             file_id: String,
+            idempotency_key: T.nilable(String),
             type: Increase::Document::Type::TaggedSymbol
           }
         )
@@ -77,6 +107,32 @@ module Increase
       def to_hash
       end
 
+      class AccountVerificationLetter < Increase::Internal::Type::BaseModel
+        OrHash =
+          T.type_alias do
+            T.any(
+              Increase::Document::AccountVerificationLetter,
+              Increase::Internal::AnyHash
+            )
+          end
+
+        # The identifier of the Account Number the document was generated for.
+        sig { returns(String) }
+        attr_accessor :account_number_id
+
+        # Properties of an account verification letter document.
+        sig { params(account_number_id: String).returns(T.attached_class) }
+        def self.new(
+          # The identifier of the Account Number the document was generated for.
+          account_number_id:
+        )
+        end
+
+        sig { override.returns({ account_number_id: String }) }
+        def to_hash
+        end
+      end
+
       # The type of document.
       module Category
         extend Increase::Internal::Type::Enum
@@ -107,6 +163,13 @@ module Increase
             Increase::Document::Category::TaggedSymbol
           )
 
+        # An account verification letter.
+        ACCOUNT_VERIFICATION_LETTER =
+          T.let(
+            :account_verification_letter,
+            Increase::Document::Category::TaggedSymbol
+          )
+
         sig do
           override.returns(T::Array[Increase::Document::Category::TaggedSymbol])
         end
diff --git a/rbi/increase/models/document_create_params.rbi b/rbi/increase/models/document_create_params.rbi
new file mode 100644
index 000000000..a4a9163b4
--- /dev/null
+++ b/rbi/increase/models/document_create_params.rbi
@@ -0,0 +1,132 @@
+# typed: strong
+
+module Increase
+  module Models
+    class DocumentCreateParams < Increase::Internal::Type::BaseModel
+      extend Increase::Internal::Type::RequestParameters::Converter
+      include Increase::Internal::Type::RequestParameters
+
+      OrHash =
+        T.type_alias do
+          T.any(Increase::DocumentCreateParams, Increase::Internal::AnyHash)
+        end
+
+      # The type of document to create.
+      sig { returns(Increase::DocumentCreateParams::Category::OrSymbol) }
+      attr_accessor :category
+
+      # An account verification letter.
+      sig do
+        returns(
+          T.nilable(Increase::DocumentCreateParams::AccountVerificationLetter)
+        )
+      end
+      attr_reader :account_verification_letter
+
+      sig do
+        params(
+          account_verification_letter:
+            Increase::DocumentCreateParams::AccountVerificationLetter::OrHash
+        ).void
+      end
+      attr_writer :account_verification_letter
+
+      sig do
+        params(
+          category: Increase::DocumentCreateParams::Category::OrSymbol,
+          account_verification_letter:
+            Increase::DocumentCreateParams::AccountVerificationLetter::OrHash,
+          request_options: Increase::RequestOptions::OrHash
+        ).returns(T.attached_class)
+      end
+      def self.new(
+        # The type of document to create.
+        category:,
+        # An account verification letter.
+        account_verification_letter: nil,
+        request_options: {}
+      )
+      end
+
+      sig do
+        override.returns(
+          {
+            category: Increase::DocumentCreateParams::Category::OrSymbol,
+            account_verification_letter:
+              Increase::DocumentCreateParams::AccountVerificationLetter,
+            request_options: Increase::RequestOptions
+          }
+        )
+      end
+      def to_hash
+      end
+
+      # The type of document to create.
+      module Category
+        extend Increase::Internal::Type::Enum
+
+        TaggedSymbol =
+          T.type_alias do
+            T.all(Symbol, Increase::DocumentCreateParams::Category)
+          end
+        OrSymbol = T.type_alias { T.any(Symbol, String) }
+
+        # An account verification letter.
+        ACCOUNT_VERIFICATION_LETTER =
+          T.let(
+            :account_verification_letter,
+            Increase::DocumentCreateParams::Category::TaggedSymbol
+          )
+
+        sig do
+          override.returns(
+            T::Array[Increase::DocumentCreateParams::Category::TaggedSymbol]
+          )
+        end
+        def self.values
+        end
+      end
+
+      class AccountVerificationLetter < Increase::Internal::Type::BaseModel
+        OrHash =
+          T.type_alias do
+            T.any(
+              Increase::DocumentCreateParams::AccountVerificationLetter,
+              Increase::Internal::AnyHash
+            )
+          end
+
+        # The Account Number the bank letter should be generated for.
+        sig { returns(String) }
+        attr_accessor :account_number_id
+
+        # If provided, the letter will include the Account's balance as of the date.
+        sig { returns(T.nilable(Date)) }
+        attr_reader :balance_date
+
+        sig { params(balance_date: Date).void }
+        attr_writer :balance_date
+
+        # An account verification letter.
+        sig do
+          params(account_number_id: String, balance_date: Date).returns(
+            T.attached_class
+          )
+        end
+        def self.new(
+          # The Account Number the bank letter should be generated for.
+          account_number_id:,
+          # If provided, the letter will include the Account's balance as of the date.
+          balance_date: nil
+        )
+        end
+
+        sig do
+          override.returns({ account_number_id: String, balance_date: Date })
+        end
+        def to_hash
+        end
+      end
+    end
+  end
+end
diff --git a/rbi/increase/models/document_list_params.rbi b/rbi/increase/models/document_list_params.rbi
index ebd7373b5..60c8a9ece 100644
--- a/rbi/increase/models/document_list_params.rbi
+++ b/rbi/increase/models/document_list_params.rbi
@@ -41,6 +41,16 @@ module Increase
       sig { params(entity_id: String).void }
       attr_writer :entity_id
 
+      # Filter records to the one with the specified `idempotency_key` you chose for
+      # that object. This value is unique across Increase and is used to ensure that a
+      # request is only processed once. Learn more about
+      # [idempotency](https://increase.com/documentation/idempotency-keys).
+      sig { returns(T.nilable(String)) }
+      attr_reader :idempotency_key
+
+      sig { params(idempotency_key: String).void }
+      attr_writer :idempotency_key
+
       # Limit the size of the list that is returned. The default (and maximum) is 100
       # objects.
       sig { returns(T.nilable(Integer)) }
@@ -55,6 +65,7 @@ module Increase
           created_at: Increase::DocumentListParams::CreatedAt::OrHash,
           cursor: String,
           entity_id: String,
+          idempotency_key: String,
           limit: Integer,
           request_options: Increase::RequestOptions::OrHash
         ).returns(T.attached_class)
@@ -66,6 +77,11 @@ module Increase
         cursor: nil,
         # Filter Documents to ones belonging to the specified Entity.
         entity_id: nil,
+        # Filter records to the one with the specified `idempotency_key` you chose for
+        # that object. This value is unique across Increase and is used to ensure that a
+        # request is only processed once. Learn more about
+        # [idempotency](https://increase.com/documentation/idempotency-keys).
+        idempotency_key: nil,
         # Limit the size of the list that is returned. The default (and maximum) is 100
         # objects.
         limit: nil,
@@ -80,6 +96,7 @@ module Increase
             created_at: Increase::DocumentListParams::CreatedAt,
             cursor: String,
             entity_id: String,
+            idempotency_key: String,
             limit: Integer,
             request_options: Increase::RequestOptions
           }
@@ -177,6 +194,13 @@ module Increase
               Increase::DocumentListParams::Category::In::TaggedSymbol
             )
 
+          # An account verification letter.
+          ACCOUNT_VERIFICATION_LETTER =
+            T.let(
+              :account_verification_letter,
+              Increase::DocumentListParams::Category::In::TaggedSymbol
+            )
+
           sig do
             override.returns(
               T::Array[Increase::DocumentListParams::Category::In::TaggedSymbol]
diff --git a/rbi/increase/models/file.rbi b/rbi/increase/models/file.rbi
index f7dc62f18..e7025edc8 100644
--- a/rbi/increase/models/file.rbi
+++ b/rbi/increase/models/file.rbi
@@ -258,6 +258,13 @@ module Increase
             Increase::File::Purpose::TaggedSymbol
           )
 
+        # An account verification letter.
+        ACCOUNT_VERIFICATION_LETTER =
+          T.let(
+            :account_verification_letter,
+            Increase::File::Purpose::TaggedSymbol
+          )
+
         sig do
           override.returns(T::Array[Increase::File::Purpose::TaggedSymbol])
         end
diff --git a/rbi/increase/models/file_list_params.rbi b/rbi/increase/models/file_list_params.rbi
index f90787b30..d0564d6e5 100644
--- a/rbi/increase/models/file_list_params.rbi
+++ b/rbi/increase/models/file_list_params.rbi
@@ -389,6 +389,13 @@ module Increase
               Increase::FileListParams::Purpose::In::TaggedSymbol
             )
 
+          # An account verification letter.
+          ACCOUNT_VERIFICATION_LETTER =
+            T.let(
+              :account_verification_letter,
+              Increase::FileListParams::Purpose::In::TaggedSymbol
+            )
+
           sig do
             override.returns(
               T::Array[Increase::FileListParams::Purpose::In::TaggedSymbol]
diff --git a/rbi/increase/resources/documents.rbi b/rbi/increase/resources/documents.rbi
index 4c69d86f9..33ff7a77d 100644
--- a/rbi/increase/resources/documents.rbi
+++ b/rbi/increase/resources/documents.rbi
@@ -3,6 +3,24 @@
 module Increase
   module Resources
     class Documents
+      # Create a Document
+      sig do
+        params(
+          category: Increase::DocumentCreateParams::Category::OrSymbol,
+          account_verification_letter:
+            Increase::DocumentCreateParams::AccountVerificationLetter::OrHash,
+          request_options: Increase::RequestOptions::OrHash
+        ).returns(Increase::Document)
+      end
+      def create(
+        # The type of document to create.
+        category:,
+        # An account verification letter.
+        account_verification_letter: nil,
+        request_options: {}
+      )
+      end
+
       # Retrieve a Document
       sig do
         params(
@@ -24,6 +42,7 @@ module Increase
           created_at: Increase::DocumentListParams::CreatedAt::OrHash,
           cursor: String,
           entity_id: String,
+          idempotency_key: String,
           limit: Integer,
           request_options: Increase::RequestOptions::OrHash
         ).returns(Increase::Internal::Page[Increase::Document])
@@ -35,6 +54,11 @@ module Increase
         cursor: nil,
         # Filter Documents to ones belonging to the specified Entity.
         entity_id: nil,
+        # Filter records to the one with the specified `idempotency_key` you chose for
+        # that object. This value is unique across Increase and is used to ensure that a
+        # request is only processed once. Learn more about
+        # [idempotency](https://increase.com/documentation/idempotency-keys).
+        idempotency_key: nil,
         # Limit the size of the list that is returned. The default (and maximum) is 100
         # objects.
         limit: nil,
diff --git a/sig/increase/models.rbs b/sig/increase/models.rbs
index 11f2f36ea..021c216a8 100644
--- a/sig/increase/models.rbs
+++ b/sig/increase/models.rbs
@@ -171,6 +171,8 @@ module Increase
 
   class Document = Increase::Models::Document
 
+  class DocumentCreateParams = Increase::Models::DocumentCreateParams
+
   class DocumentListParams = Increase::Models::DocumentListParams
 
   class DocumentRetrieveParams = Increase::Models::DocumentRetrieveParams
diff --git a/sig/increase/models/document.rbs b/sig/increase/models/document.rbs
index 6a12ff556..bf45dd0ce 100644
--- a/sig/increase/models/document.rbs
+++ b/sig/increase/models/document.rbs
@@ -3,16 +3,20 @@ module Increase
     type document =
       {
         id: String,
+        account_verification_letter: Increase::Document::AccountVerificationLetter?,
         category: Increase::Models::Document::category,
         created_at: Time,
         entity_id: String?,
         file_id: String,
+        idempotency_key: String?,
         type: Increase::Models::Document::type_
       }
 
     class Document < Increase::Internal::Type::BaseModel
       attr_accessor id: String
 
+      attr_accessor account_verification_letter: Increase::Document::AccountVerificationLetter?
+
       attr_accessor category: Increase::Models::Document::category
 
       attr_accessor created_at: Time
@@ -21,31 +25,48 @@ module Increase
 
       attr_accessor file_id: String
 
+      attr_accessor idempotency_key: String?
+
       attr_accessor type: Increase::Models::Document::type_
 
       def initialize: (
         id: String,
+        account_verification_letter: Increase::Document::AccountVerificationLetter?,
         category: Increase::Models::Document::category,
         created_at: Time,
         entity_id: String?,
         file_id: String,
+        idempotency_key: String?,
         type: Increase::Models::Document::type_
       ) -> void
 
       def to_hash: -> {
         id: String,
+        account_verification_letter: Increase::Document::AccountVerificationLetter?,
         category: Increase::Models::Document::category,
         created_at: Time,
         entity_id: String?,
         file_id: String,
+        idempotency_key: String?,
         type: Increase::Models::Document::type_
       }
 
+      type account_verification_letter = { account_number_id: String }
+
+      class AccountVerificationLetter < Increase::Internal::Type::BaseModel
+        attr_accessor account_number_id: String
+
+        def initialize: (account_number_id: String) -> void
+
+        def to_hash: -> { account_number_id: String }
+      end
+
       type category =
         :form_1099_int
         | :form_1099_misc
         | :proof_of_authorization
         | :company_information
+        | :account_verification_letter
 
       module Category
         extend Increase::Internal::Type::Enum
@@ -62,6 +83,9 @@ module Increase
         # Company information, such a policies or procedures, typically submitted during our due diligence process.
         COMPANY_INFORMATION: :company_information
 
+        # An account verification letter.
+        ACCOUNT_VERIFICATION_LETTER: :account_verification_letter
+
         def self?.values: -> ::Array[Increase::Models::Document::category]
       end
 
diff --git a/sig/increase/models/document_create_params.rbs b/sig/increase/models/document_create_params.rbs
new file mode 100644
index 000000000..d667ea47c
--- /dev/null
+++ b/sig/increase/models/document_create_params.rbs
@@ -0,0 +1,61 @@
+module Increase
+  module Models
+    type document_create_params =
+      {
+        category: Increase::Models::DocumentCreateParams::category,
+        account_verification_letter: Increase::DocumentCreateParams::AccountVerificationLetter
+      }
+      & Increase::Internal::Type::request_parameters
+
+    class DocumentCreateParams < Increase::Internal::Type::BaseModel
+      extend Increase::Internal::Type::RequestParameters::Converter
+      include Increase::Internal::Type::RequestParameters
+
+      attr_accessor category: Increase::Models::DocumentCreateParams::category
+
+      attr_reader account_verification_letter: Increase::DocumentCreateParams::AccountVerificationLetter?
+
+      def account_verification_letter=: (
+        Increase::DocumentCreateParams::AccountVerificationLetter
+      ) -> Increase::DocumentCreateParams::AccountVerificationLetter
+
+      def initialize: (
+        category: Increase::Models::DocumentCreateParams::category,
+        ?account_verification_letter: Increase::DocumentCreateParams::AccountVerificationLetter,
+        ?request_options: Increase::request_opts
+      ) -> void
+
+      def to_hash: -> {
+        category: Increase::Models::DocumentCreateParams::category,
+        account_verification_letter: Increase::DocumentCreateParams::AccountVerificationLetter,
+        request_options: Increase::RequestOptions
+      }
+
+      type category = :account_verification_letter
+
+      module Category
+        extend Increase::Internal::Type::Enum
+
+        # An account verification letter.
+        ACCOUNT_VERIFICATION_LETTER: :account_verification_letter
+
+        def self?.values: -> ::Array[Increase::Models::DocumentCreateParams::category]
+      end
+
+      type account_verification_letter =
+        { account_number_id: String, balance_date: Date }
+
+      class AccountVerificationLetter < Increase::Internal::Type::BaseModel
+        attr_accessor account_number_id: String
+
+        attr_reader balance_date: Date?
+
+        def balance_date=: (Date) -> Date
+
+        def initialize: (account_number_id: String, ?balance_date: Date) -> void
+
+        def to_hash: -> { account_number_id: String, balance_date: Date }
+      end
+    end
+  end
+end
diff --git a/sig/increase/models/document_list_params.rbs b/sig/increase/models/document_list_params.rbs
index f14106db3..f22754ee3 100644
--- a/sig/increase/models/document_list_params.rbs
+++ b/sig/increase/models/document_list_params.rbs
@@ -6,6 +6,7 @@ module Increase
         created_at: Increase::DocumentListParams::CreatedAt,
         cursor: String,
         entity_id: String,
+        idempotency_key: String,
         limit: Integer
       }
       & Increase::Internal::Type::request_parameters
@@ -34,6 +35,10 @@ module Increase
 
       def entity_id=: (String) -> String
 
+      attr_reader idempotency_key: String?
+
+      def idempotency_key=: (String) -> String
+
       attr_reader limit: Integer?
 
       def limit=: (Integer) -> Integer
@@ -43,6 +48,7 @@ module Increase
         ?created_at: Increase::DocumentListParams::CreatedAt,
         ?cursor: String,
         ?entity_id: String,
+        ?idempotency_key: String,
         ?limit: Integer,
         ?request_options: Increase::request_opts
       ) -> void
@@ -52,6 +58,7 @@ module Increase
         created_at: Increase::DocumentListParams::CreatedAt,
         cursor: String,
         entity_id: String,
+        idempotency_key: String,
         limit: Integer,
         request_options: Increase::RequestOptions
       }
@@ -79,6 +86,7 @@ module Increase
           | :form_1099_misc
           | :proof_of_authorization
           | :company_information
+          | :account_verification_letter
 
         module In
           extend Increase::Internal::Type::Enum
@@ -95,6 +103,9 @@ module Increase
           # Company information, such a policies or procedures, typically submitted during our due diligence process.
           COMPANY_INFORMATION: :company_information
 
+          # An account verification letter.
+          ACCOUNT_VERIFICATION_LETTER: :account_verification_letter
+
           def self?.values: -> ::Array[Increase::Models::DocumentListParams::Category::in_]
         end
       end
diff --git a/sig/increase/models/file.rbs b/sig/increase/models/file.rbs
index 3020ba96f..5705f19d0 100644
--- a/sig/increase/models/file.rbs
+++ b/sig/increase/models/file.rbs
@@ -96,6 +96,7 @@ module Increase
         | :unusual_activity_report_attachment
         | :deposit_account_control_agreement
         | :proof_of_authorization_request_submission
+        | :account_verification_letter
 
       module Purpose
         extend Increase::Internal::Type::Enum
@@ -175,6 +176,9 @@ module Increase
         # A file containing additional evidence for a Proof of Authorization Request Submission.
         PROOF_OF_AUTHORIZATION_REQUEST_SUBMISSION: :proof_of_authorization_request_submission
 
+        # An account verification letter.
+        ACCOUNT_VERIFICATION_LETTER: :account_verification_letter
+
         def self?.values: -> ::Array[Increase::Models::File::purpose]
       end
 
diff --git a/sig/increase/models/file_list_params.rbs b/sig/increase/models/file_list_params.rbs
index 0beb92d4d..679c0975d 100644
--- a/sig/increase/models/file_list_params.rbs
+++ b/sig/increase/models/file_list_params.rbs
@@ -135,6 +135,7 @@ module Increase
           | :unusual_activity_report_attachment
           | :deposit_account_control_agreement
           | :proof_of_authorization_request_submission
+          | :account_verification_letter
 
         module In
           extend Increase::Internal::Type::Enum
@@ -214,6 +215,9 @@ module Increase
           # A file containing additional evidence for a Proof of Authorization Request Submission.
           PROOF_OF_AUTHORIZATION_REQUEST_SUBMISSION: :proof_of_authorization_request_submission
 
+          # An account verification letter.
+          ACCOUNT_VERIFICATION_LETTER: :account_verification_letter
+
           def self?.values: -> ::Array[Increase::Models::FileListParams::Purpose::in_]
         end
       end
diff --git a/sig/increase/resources/documents.rbs b/sig/increase/resources/documents.rbs
index cde2f6f82..868deeded 100644
--- a/sig/increase/resources/documents.rbs
+++ b/sig/increase/resources/documents.rbs
@@ -1,6 +1,12 @@
 module Increase
   module Resources
     class Documents
+      def create: (
+        category: Increase::Models::DocumentCreateParams::category,
+        ?account_verification_letter: Increase::DocumentCreateParams::AccountVerificationLetter,
+        ?request_options: Increase::request_opts
+      ) -> Increase::Document
+
       def retrieve: (
         String document_id,
         ?request_options: Increase::request_opts
@@ -11,6 +17,7 @@ module Increase
         ?created_at: Increase::DocumentListParams::CreatedAt,
         ?cursor: String,
         ?entity_id: String,
+        ?idempotency_key: String,
         ?limit: Integer,
         ?request_options: Increase::request_opts
       ) -> Increase::Internal::Page[Increase::Document]
diff --git a/test/increase/resources/documents_test.rb b/test/increase/resources/documents_test.rb
index c26aeaa76..9742598ee 100644
--- a/test/increase/resources/documents_test.rb
+++ b/test/increase/resources/documents_test.rb
@@ -3,6 +3,27 @@
 require_relative "../test_helper"
 
 class Increase::Test::Resources::DocumentsTest < Increase::Test::ResourceTest
+  def test_create_required_params
+    response = @increase.documents.create(category: :account_verification_letter)
+
+    assert_pattern do
+      response => Increase::Document
+    end
+
+    assert_pattern do
+      response => {
+        id: String,
+        account_verification_letter: Increase::Document::AccountVerificationLetter | nil,
+        category: Increase::Document::Category,
+        created_at: Time,
+        entity_id: String | nil,
+        file_id: String,
+        idempotency_key: String | nil,
+        type: Increase::Document::Type
+      }
+    end
+  end
+
   def test_retrieve
     response = @increase.documents.retrieve("document_id")
 
@@ -13,10 +34,12 @@ def test_retrieve
     assert_pattern do
       response => {
         id: String,
+        account_verification_letter: Increase::Document::AccountVerificationLetter | nil,
         category: Increase::Document::Category,
         created_at: Time,
         entity_id: String | nil,
         file_id: String,
+        idempotency_key: String | nil,
         type: Increase::Document::Type
       }
     end
@@ -39,10 +62,12 @@ def test_list
     assert_pattern do
       row => {
         id: String,
+        account_verification_letter: Increase::Document::AccountVerificationLetter | nil,
         category: Increase::Document::Category,
         created_at: Time,
         entity_id: String | nil,
         file_id: String,
+        idempotency_key: String | nil,
         type: Increase::Document::Type
       }
     end
diff --git a/test/increase/resources/simulations/documents_test.rb b/test/increase/resources/simulations/documents_test.rb
index c6e9d1a85..c04de69d6 100644
--- a/test/increase/resources/simulations/documents_test.rb
+++ b/test/increase/resources/simulations/documents_test.rb
@@ -13,10 +13,12 @@ def test_create_required_params
     assert_pattern do
       response => {
         id: String,
+        account_verification_letter: Increase::Document::AccountVerificationLetter | nil,
         category: Increase::Document::Category,
         created_at: Time,
         entity_id: String | nil,
         file_id: String,
+        idempotency_key: String | nil,
         type: Increase::Document::Type
       }
     end