diff --git a/hledger-web/config/openapi.yaml b/hledger-web/config/openapi.yaml
new file mode 100644
index 000000000..dad2d08b9
--- /dev/null
+++ b/hledger-web/config/openapi.yaml
@@ -0,0 +1,561 @@
+openapi: 3.1.0
+info:
+  title: OpenAPI Specification
+  description: "Basic description of [hledger-web's JSON-over-HTTP API](https://hledger.org/hledger-web.html#json-api).\
+    \ A specification generated by [openapi-devtools](https://github.com/AndrewWalsh/openapi-devtools).\
+    \ Contains 7 endpoints."
+  version: 1.0.0
+servers:
+- url: /
+paths:
+  /version:
+    get:
+      summary: /version
+      description: "**Host**: http://127.0.0.1:5000"
+      responses:
+        "200":
+          description: ""
+          content:
+            application/json:
+              schema: {}
+      security:
+      - apikey_cookie__session: []
+      - apikey_header_cookie: []
+  /accountnames:
+    get:
+      summary: /accountnames
+      description: "**Host**: http://127.0.0.1:5000"
+      responses:
+        "200":
+          description: ""
+          content:
+            application/json:
+              schema:
+                items: {}
+      security:
+      - apikey_cookie__session: []
+      - apikey_header_cookie: []
+  /transactions:
+    get:
+      summary: /transactions
+      description: "**Host**: http://127.0.0.1:5000"
+      responses:
+        "200":
+          description: ""
+          content:
+            application/json:
+              schema:
+                items:
+                  required:
+                  - tcode
+                  - tcomment
+                  - tdate
+                  - tdate2
+                  - tdescription
+                  - tindex
+                  - tpostings
+                  - tprecedingcomment
+                  - tsourcepos
+                  - tstatus
+                  - ttags
+                  properties:
+                    tcode: {}
+                    tcomment: {}
+                    tdate: {}
+                    tdate2: {}
+                    tdescription: {}
+                    tindex: {}
+                    tpostings:
+                      items:
+                        required:
+                        - paccount
+                        - pamount
+                        - pbalanceassertion
+                        - pcomment
+                        - pdate
+                        - pdate2
+                        - poriginal
+                        - pstatus
+                        - ptags
+                        - ptransaction_
+                        - ptype
+                        properties:
+                          paccount: {}
+                          pamount:
+                            items:
+                              required:
+                              - acommodity
+                              - acost
+                              - aquantity
+                              - astyle
+                              properties:
+                                acommodity: {}
+                                acost:
+                                  anyOf:
+                                  - {}
+                                  - required:
+                                    - contents
+                                    - tag
+                                    properties:
+                                      contents:
+                                        required:
+                                        - acommodity
+                                        - acost
+                                        - aquantity
+                                        - astyle
+                                        properties:
+                                          acommodity: {}
+                                          acost: {}
+                                          aquantity:
+                                            required:
+                                            - decimalMantissa
+                                            - decimalPlaces
+                                            - floatingPoint
+                                            properties:
+                                              decimalMantissa: {}
+                                              decimalPlaces: {}
+                                              floatingPoint: {}
+                                          astyle:
+                                            required:
+                                            - ascommodityside
+                                            - ascommodityspaced
+                                            - asdecimalmark
+                                            - asdigitgroups
+                                            - asprecision
+                                            - asrounding
+                                            properties:
+                                              ascommodityside: {}
+                                              ascommodityspaced: {}
+                                              asdecimalmark: {}
+                                              asdigitgroups: {}
+                                              asprecision: {}
+                                              asrounding: {}
+                                      tag: {}
+                                aquantity:
+                                  required:
+                                  - decimalMantissa
+                                  - decimalPlaces
+                                  - floatingPoint
+                                  properties:
+                                    decimalMantissa: {}
+                                    decimalPlaces: {}
+                                    floatingPoint: {}
+                                astyle:
+                                  required:
+                                  - ascommodityside
+                                  - ascommodityspaced
+                                  - asdecimalmark
+                                  - asdigitgroups
+                                  - asprecision
+                                  - asrounding
+                                  properties:
+                                    ascommodityside: {}
+                                    ascommodityspaced: {}
+                                    asdecimalmark: {}
+                                    asdigitgroups: {}
+                                    asprecision: {}
+                                    asrounding: {}
+                          pbalanceassertion: {}
+                          pcomment: {}
+                          pdate: {}
+                          pdate2: {}
+                          poriginal: {}
+                          pstatus: {}
+                          ptags: {}
+                          ptransaction_: {}
+                          ptype: {}
+                    tprecedingcomment: {}
+                    tsourcepos:
+                      items:
+                        required:
+                        - sourceColumn
+                        - sourceLine
+                        - sourceName
+                        properties:
+                          sourceColumn: {}
+                          sourceLine: {}
+                          sourceName: {}
+                    tstatus: {}
+                    ttags: {}
+      security:
+      - apikey_cookie__session: []
+      - apikey_header_cookie: []
+  /prices:
+    get:
+      summary: /prices
+      description: "**Host**: http://127.0.0.1:5000"
+      responses:
+        "200":
+          description: ""
+          content:
+            application/json:
+              schema:
+                items:
+                  required:
+                  - mpdate
+                  - mpfrom
+                  - mprate
+                  - mpto
+                  properties:
+                    mpdate: {}
+                    mpfrom: {}
+                    mprate:
+                      required:
+                      - decimalMantissa
+                      - decimalPlaces
+                      - floatingPoint
+                      properties:
+                        decimalMantissa: {}
+                        decimalPlaces: {}
+                        floatingPoint: {}
+                    mpto: {}
+      security:
+      - apikey_cookie__session: []
+      - apikey_header_cookie: []
+  /commodities:
+    get:
+      summary: /commodities
+      description: "**Host**: http://127.0.0.1:5000"
+      responses:
+        "200":
+          description: ""
+          content:
+            application/json:
+              schema:
+                items: {}
+      security:
+      - apikey_cookie__session: []
+      - apikey_header_cookie: []
+  /accounts:
+    get:
+      summary: /accounts
+      description: "**Host**: http://127.0.0.1:5000"
+      responses:
+        "200":
+          description: ""
+          content:
+            application/json:
+              schema:
+                items:
+                  required:
+                  - aboring
+                  - adeclarationinfo
+                  - aebalance
+                  - aibalance
+                  - aname
+                  - anumpostings
+                  - aparent_
+                  - asubs
+                  - asubs_
+                  properties:
+                    aname: {}
+                    adeclarationinfo: {}
+                    aebalance:
+                      items:
+                        required:
+                        - acommodity
+                        - acost
+                        - aquantity
+                        - astyle
+                        properties:
+                          acommodity: {}
+                          acost:
+                            anyOf:
+                            - {}
+                            - required:
+                              - contents
+                              - tag
+                              properties:
+                                contents:
+                                  required:
+                                  - acommodity
+                                  - acost
+                                  - aquantity
+                                  - astyle
+                                  properties:
+                                    acommodity: {}
+                                    acost: {}
+                                    aquantity:
+                                      required:
+                                      - decimalMantissa
+                                      - decimalPlaces
+                                      - floatingPoint
+                                      properties:
+                                        decimalMantissa: {}
+                                        decimalPlaces: {}
+                                        floatingPoint: {}
+                                    astyle:
+                                      required:
+                                      - ascommodityside
+                                      - ascommodityspaced
+                                      - asdecimalmark
+                                      - asdigitgroups
+                                      - asprecision
+                                      - asrounding
+                                      properties:
+                                        ascommodityside: {}
+                                        ascommodityspaced: {}
+                                        asdecimalmark: {}
+                                        asdigitgroups: {}
+                                        asprecision: {}
+                                        asrounding: {}
+                                tag: {}
+                          aquantity:
+                            required:
+                            - decimalMantissa
+                            - decimalPlaces
+                            - floatingPoint
+                            properties:
+                              decimalMantissa: {}
+                              decimalPlaces: {}
+                              floatingPoint: {}
+                          astyle:
+                            required:
+                            - ascommodityside
+                            - ascommodityspaced
+                            - asdecimalmark
+                            - asdigitgroups
+                            - asprecision
+                            - asrounding
+                            properties:
+                              ascommodityside: {}
+                              ascommodityspaced: {}
+                              asdecimalmark: {}
+                              asdigitgroups: {}
+                              asprecision: {}
+                              asrounding: {}
+                    aibalance:
+                      items:
+                        required:
+                        - acommodity
+                        - acost
+                        - aquantity
+                        - astyle
+                        properties:
+                          acommodity: {}
+                          acost:
+                            anyOf:
+                            - {}
+                            - required:
+                              - contents
+                              - tag
+                              properties:
+                                contents:
+                                  required:
+                                  - acommodity
+                                  - acost
+                                  - aquantity
+                                  - astyle
+                                  properties:
+                                    acommodity: {}
+                                    acost: {}
+                                    aquantity:
+                                      required:
+                                      - decimalMantissa
+                                      - decimalPlaces
+                                      - floatingPoint
+                                      properties:
+                                        decimalMantissa: {}
+                                        decimalPlaces: {}
+                                        floatingPoint: {}
+                                    astyle:
+                                      required:
+                                      - ascommodityside
+                                      - ascommodityspaced
+                                      - asdecimalmark
+                                      - asdigitgroups
+                                      - asprecision
+                                      - asrounding
+                                      properties:
+                                        ascommodityside: {}
+                                        ascommodityspaced: {}
+                                        asdecimalmark: {}
+                                        asdigitgroups: {}
+                                        asprecision: {}
+                                        asrounding: {}
+                                tag: {}
+                          aquantity:
+                            required:
+                            - decimalMantissa
+                            - decimalPlaces
+                            - floatingPoint
+                            properties:
+                              decimalMantissa: {}
+                              decimalPlaces: {}
+                              floatingPoint: {}
+                          astyle:
+                            required:
+                            - ascommodityside
+                            - ascommodityspaced
+                            - asdecimalmark
+                            - asdigitgroups
+                            - asprecision
+                            - asrounding
+                            properties:
+                              ascommodityside: {}
+                              ascommodityspaced: {}
+                              asdecimalmark: {}
+                              asdigitgroups: {}
+                              asprecision: {}
+                              asrounding: {}
+                    anumpostings: {}
+                    aboring: {}
+                    aparent_: {}
+                    asubs_:
+                      items: {}
+                    asubs: {}
+      security:
+      - apikey_cookie__session: []
+      - apikey_header_cookie: []
+  /accounttransactions/1:
+    get:
+      summary: /accounttransactions/1
+      description: "**Host**: http://127.0.0.1:5000"
+      responses:
+        "200":
+          description: ""
+          content:
+            application/json:
+              schema:
+                items:
+                  items:
+                    anyOf:
+                    - {}
+                    - items:
+                        required:
+                        - acommodity
+                        - acost
+                        - aquantity
+                        - astyle
+                        properties:
+                          acommodity: {}
+                          acost: {}
+                          aquantity:
+                            required:
+                            - decimalMantissa
+                            - decimalPlaces
+                            - floatingPoint
+                            properties:
+                              decimalMantissa: {}
+                              decimalPlaces: {}
+                              floatingPoint: {}
+                          astyle:
+                            required:
+                            - ascommodityside
+                            - ascommodityspaced
+                            - asdecimalmark
+                            - asdigitgroups
+                            - asprecision
+                            - asrounding
+                            properties:
+                              ascommodityside: {}
+                              ascommodityspaced: {}
+                              asdecimalmark: {}
+                              asdigitgroups: {}
+                              asprecision: {}
+                              asrounding: {}
+                    - required:
+                      - tcode
+                      - tcomment
+                      - tdate
+                      - tdate2
+                      - tdescription
+                      - tindex
+                      - tpostings
+                      - tprecedingcomment
+                      - tsourcepos
+                      - tstatus
+                      - ttags
+                      properties:
+                        tcode: {}
+                        tcomment: {}
+                        tdate: {}
+                        tdate2: {}
+                        tdescription: {}
+                        tindex: {}
+                        tpostings:
+                          items:
+                            required:
+                            - paccount
+                            - pamount
+                            - pbalanceassertion
+                            - pcomment
+                            - pdate
+                            - pdate2
+                            - poriginal
+                            - pstatus
+                            - ptags
+                            - ptransaction_
+                            - ptype
+                            properties:
+                              paccount: {}
+                              pamount:
+                                items:
+                                  required:
+                                  - acommodity
+                                  - acost
+                                  - aquantity
+                                  - astyle
+                                  properties:
+                                    acommodity: {}
+                                    acost: {}
+                                    aquantity:
+                                      required:
+                                      - decimalMantissa
+                                      - decimalPlaces
+                                      - floatingPoint
+                                      properties:
+                                        decimalMantissa: {}
+                                        decimalPlaces: {}
+                                        floatingPoint: {}
+                                    astyle:
+                                      required:
+                                      - ascommodityside
+                                      - ascommodityspaced
+                                      - asdecimalmark
+                                      - asdigitgroups
+                                      - asprecision
+                                      - asrounding
+                                      properties:
+                                        ascommodityside: {}
+                                        ascommodityspaced: {}
+                                        asdecimalmark: {}
+                                        asdigitgroups: {}
+                                        asprecision: {}
+                                        asrounding: {}
+                              pbalanceassertion: {}
+                              pcomment: {}
+                              pdate: {}
+                              pdate2: {}
+                              poriginal: {}
+                              pstatus: {}
+                              ptags: {}
+                              ptransaction_: {}
+                              ptype: {}
+                        tprecedingcomment: {}
+                        tsourcepos:
+                          items:
+                            required:
+                            - sourceColumn
+                            - sourceLine
+                            - sourceName
+                            properties:
+                              sourceColumn: {}
+                              sourceLine: {}
+                              sourceName: {}
+                        tstatus: {}
+                        ttags: {}
+      security:
+      - apikey_cookie__session: []
+      - apikey_header_cookie: []
+components:
+  schemas: {}
+  securitySchemes:
+    apikey_cookie__session:
+      type: apiKey
+      name: _session
+      in: cookie
+    apikey_header_cookie:
+      type: apiKey
+      name: COOKIE
+      in: header