Introduction

Last updated: August 2026

Welcome to the General Index documentation site. This site contains the information required to submit and extract data from the General Index system, including file formats and API specifications.

For questions regarding integrating GX data into your systems and submitting data, please contact support@general-index.com.

Methodology Framework

GX generates pricing assessments under a standard set of procedures that is mathematical, consistent and fully transparent. This is defined in the GX Methodology Framework, available online.

This documentation does not take precedence over the Methodology Framework or any contractual agreements in place.

Data Notices

GX sends out ad-hoc data notices containing information on new data series, updates to metadata and corrections that apply to data more than 30 days old. We encourage all users of GX data to sign-up to receive these notices. New users can sign-up here:

https://pages.general-index.com/datanotices

Index Modules

Index Series are grouped for licensing and access via Index Modules. Index Modules correspond to trading hubs and/or commodities.

Example Index Modules:

GlobalIndexes

NorthAmericaCrude

EuropeanCrude

EuropeanGasoline

EuropeanJet

There are currently around 60 Index Modules covering crude, refined products, marine fuels, natural gas, biofuels, carbon and power markets.

All data within a single Index Module is available to licensed users including all GX index series, index types, forward periods and timestamps for that Module.

Individual Index Series may be contained within multiple Index Modules.

The mapping of Index Series to Index Modules is published in the IndexModule column of the Data Catalogue. A series that belongs to more than one Module appears once per Module.

Time zones

Please note: All times and dates associated with Index Series are subject to time zones. Time zones are specified in metadata and are as provided in the IANA Time Zone Database (so, for example Europe/London)

Index Series Format

Last updated: August 2026

This section describes how GX Index Series are defined. It outlines standard data fields and file structures that are available across GX systems.

GX Index Codes

GX assigns a unique identifier to each Index Series – each identifier consists of the letters ‘GX’ followed by 7 digits (e.g. GX0000001), along with a title describing the content of the series (e.g. Global Crude Index (GCX) London Assessments).

Index Methodology Factsheets

A full definition of each index series is documented within the relevant factsheet. Factsheets include time zone, units of measure, location, pricing basis and calculation methodology.

Factsheet access

PDF versions of the factsheets are available from the factsheet server via this URL

https://factsheets.g-x.co/[GX_CODE].pdf

So, for example, the factsheet for Global Crude Index (GCX) London Assessments can be obtained from https://factsheets.g-x.co/GX0000001.pdf

Factsheet content is also available as JSON, for integrations that need it programmatically.

# List factsheets for a module
curl "https://api.g-x.co/factsheets?module=EuropeanGasoline" \
     -H 'Authorization: ApiKey [YourGXApiKey]'

# Full factsheet detail for one or more codes
curl "https://api.g-x.co/factsheets/details?code=GX0000004" \
     -H 'Authorization: ApiKey [YourGXApiKey]'

GET https://api.g-x.co/factsheets

GET https://api.g-x.co/factsheets/details

Returns the full factsheet record including aliases, description, methodology and metadata.

Index Keys

Each series has several time series associated with it. Individual time series are defined by the following keys. All keys are stored as text fields.

Index Types

For a specific key combination (Index code at a particular TimeRef, Period, PeriodType), GX produces values for Index Types as defined by the factsheet, for example to denote Mid, High and Low.

Decimal places and precision of numerical fields are defined in the factsheet.

Additional Columns & Metadata

All GX codes carry the following columns:

In addition to the value columns, metadata from the factsheet is provided to aid the consumption of the Index Series:

Holiday Calendars

curl "https://api.g-x.co/index?group=Meta_Holiday_Calendars&from=all&metadata=true" \
     -H 'Authorization: Bearer [YourGXAccessToken]'

GX maintains a list of holiday calendars for GX Index Series and third-party timeseries. Calendar files have the following format:

Holiday calendars can be queried through the API. Please see example. The holiday calendar should be queried in UTC time zone and the time component of the Date field ignored in the response.

Absolute Period Format

The granularity of absolute assessment periods (and held in PeriodAbs) is defined by the factsheet. Absolute assessment periods are published in the following format:

API Specification

Authorisation

Last updated: August 2026

General Index provides multiple ways to authenticate:

• API key in the Authorization header (preferred)
• API key passed as URL parameter
• Basic token passed as URL parameter
• Basic token in Header
• JWT bearer access token in Header (legacy)

API key

GX Go users can generate their own API keys:

1. Sign in to GX Go at https://go.g-x.co
2. Click your name at the bottom of the left sidebar, then Settings
3. Go to the Token Generation section and generate a new key

The name you give a key is for your own reference. Existing keys are listed with a copy button, so a key can be retrieved at any time. Keys can also be removed from the same screen.

If you do not have access to GX Go, contact GX Support for an API key.

Header authentication

# API key in the Authorization header - works on every endpoint
curl "https://api.g-x.co/index?code=GX0000004&from=5d" \
     -H 'Authorization: ApiKey [YourGXApiKey]'

Authorization: ApiKey is the recommended scheme. It works on every endpoint.

URL authentication

Basic token

# Basic token passed in url
# The token used in the example was generated for user@user.com:password
curl "https://api.g-x.co/index?token=dXNlckB1c2VyLmNvbTpwYXNzd29yZA=="

A basic token is generated from the username and password, Base64 encoded separated by a colon. It can be generated from command line, for example in macOS / Linux:
echo -n "username:password" | base64

Username and password

When an account is created, GX sends an invitation email to the address provided. Follow the link in that email to set your password. Contact GX Support if you need it reset.

Legacy JWT authentication

Log in

This endpoint returns a jwt access token and a refresh token. When access token is expired, refresh token can be used to generate a new one.

curl -u 'login:password' 
  https://api.g-x.co/auth/login

If successful, the above command returns a status code 200 and token, otherwise please check Errors section.

{
    "token": "YourGXAccessToken",
    "refreshToken": "your refresh token"
}

HTTP Request

GET https://api.g-x.co/auth/login

Request Body

Refresh Access Token

This endpoint returns a new access token.

curl -X POST
  https://api.g-x.co/auth/refresh
  -d '{
    "refreshToken": "your refresh token"
    }'

If successful, the above command returns a status code 200 and token, otherwise please check Errors section.

{
    "token": "YourGXAccessToken",
    "refreshToken": "your refresh token"
}

HTTP Request

POST https://api.g-x.co/auth/refresh

Request Body

your refresh token

Log out

Log out the user by invalidating the refresh token.

curl -X POST
  https://api.g-x.co/auth/logout
  -H "Authorization: Bearer YourGXAccessToken"
  -d '{
    "refreshToken": "your refresh token"
    }'

If successful, the above command returns status code 200, otherwise please check Errors section.

HTTP Request

POST https://api.g-x.co/auth/logout

Data Catalogue

Last updated: August 2026

Catalogue Endpoint

curl "https://api.g-x.co/catalogue?module=EuropeanGasoline \
     -H 'Authorization: Bearer [YourGXAccessToken]'

The above command returns a CSV response
Code,PeriodType,TimeRef,IndexModule,Alias,Bid,Commodity,Currency,DeliveryBasis,EndDate,FactsheetVersion,Frequency,Group,High,HolidayCalendar,Increment,Index,InterAffiliateDataAccepted,LastTradeDateCalendar,LaunchDate,Low,MapLocation,MapZoom,Method,Mid,Offer,ParentCodes,PeriodMax,PeriodMin,PermissionLatestStatus,Precision,PricingBasis,PriorityToTransactions,SoleSourcedDataAccepted,Source,StartDate,Status,ThirdPartyMappings,TimeRefDetails,TimeZone,Title,TradingHub,Units
GX0000614,Month,1630,EuropeanGasoline,EBOB1V6M,,Gasoline,USD,FOB Barges,,1.0,Daily,Prod_Indexes,,Holidays_GX_Europe,0.25,Y,N,CalendarMonth,2021-06-11,,51.9244 4.4778,7,,,,GX0000002 GX0000002,1,1,PRIMARY,2,Diff,N,N,GX,2021-02-25,Live,LSEG:GX0000614L1630c1 Bloomberg:GIOS0614 Index,London Close,Europe/London,Eurobob Oxy Gasoline NWE FOB Barges (E5) M1 vs M6,NWE,MT
GX0000472,Prompt,1630,EuropeanGasoline,,,Gasoline,USD,CIF Cargoes,,1.0,Monthly,Prod_Indexes,Y,Holidays_GX_Europe,0.0001,,N,Null,2021-06-11,Y,,,,Y,,,1,1,PRIMARY,4,Flat,N,N,GX,2008-01-31,Live,LSEG:GX0000472L1630P Platts:AAWZB03 Bloomberg:GIOS0472 Index,London Close,Europe/London,Gasoline 95 RON MED CIF Cargoes Monthly Average (MAVG),MED,MT

HTTP Request

GET https://api.g-x.co/catalogue

The endpoint returns a list of all available Index data series. URL parameters allows filtering data by Module.

URL Parameters

Response Columns

Trade Calendars

Last updated: August 2026

Trade calendars define contract expiry for index series that reference a forward contract. The calendar applicable to a series is published in the LastTradeDateCalendar column of the Data Catalogue.

# List available trade calendars
curl "https://api.g-x.co/trade/calendars" \
     -H 'Authorization: ApiKey [YourGXApiKey]'

# Which contract is live on a given date
curl "https://api.g-x.co/trade/calendars/CalendarMonth/contract?date=2026-08-21" \
     -H 'Authorization: ApiKey [YourGXApiKey]'

The above returns a JSON response

{
    "validUntil": "2026-08-31T00:00:00",
    "contract": "2026-09",
    "calendarName": "CalendarMonth"
}

List trade calendars

GET https://api.g-x.co/trade/calendars

Returns the name of every available trade calendar.

Preview a trade calendar

GET https://api.g-x.co/trade/calendars/[tradeCalendarName]

Returns every contract in the calendar with the date it is valid until.

Get contract date

GET https://api.g-x.co/trade/calendars/[tradeCalendarName]/contract

Returns the contract live on a given date.

Data Structure

Indexes are stored as timeseries data with associated symbols, metadata and values

Symbols

Individual time series are accessible through the following keys. A combination of symbols uniquely defines a time series. Symbol fields are case sensitive and are returned as text strings.

Metadata

The Fields listed below represent the standard metadata published for all Index Series. Additional Metadata is available for individual Index Series where appropriate. Note Field names are case sensitive.

Values

The Fields listed below represent the standard timeseries values associated with each Index Series. Additional Value series are available where appropriate – in particular reflecting multiple Index Value series. All field names are case sensitive.

Pull Index Data Series

Index Endpoint

The endpoint retrieves index timeseries data in the provided time range. URL parameters allows filtering data by Code or metadata fields, and selecting specific columns to return in the response.

HTTP Request

curl "https://api.g-x.co/index?code=GX0000004&metadata=true" \
     -H 'Authorization: Bearer [YourGXAccessToken]'

The above command returns a CSV response
Code,Period,PeriodType,TimeRef,Date(UTC),FactsheetVersion,High,Low,Mid,PeriodAbs(S),PeriodEnd(D),PeriodRel(S),PeriodStart(D),RecordStatus(S),Alias(MD-S),Commodity(MD-S),Currency(MD-S),DeliveryBasis(MD-S),Frequency(MD-S),HolidayCalendar(MD-S),PricingBasis(MD-S),Source(MD-S),TimeZone(MD-S),Title(MD-S),TradingHub(MD-S),Units(MD-S)
GX0000004,1,Prompt,1730,2022-11-29T17:30:00,2,774.75,774.25,774.5,Prompt,2022-12-07T23:59:59,1,2022-12-01T00:00:00,N,EUROBOBNONC,Gasoline,USD,FOB Barges,Daily,Holidays_GX_Europe,Flat,GX,Europe/London,Eurobob Non Oxy Gasoline NWE FOB Barges,NWE,MT
GX0000004,1,Prompt,1630,2022-11-29T16:30:00,1,774.75,774.25,774.5,Prompt,2022-12-07T23:59:59,1,2022-12-01T00:00:00,N,,Gasoline,USD,FOB Barges,Daily,Holidays_GX_Europe,Flat,GX,Europe/London,Eurobob Non Oxy Gasoline NWE FOB Barges,NWE,MT
GX0000004,1,Prompt,1730,2022-11-28T17:30:00,2,732.25,731.75,732,Prompt,2022-12-06T23:59:59,1,2022-11-30T00:00:00,N,EUROBOBNONC,Gasoline,USD,FOB Barges,Daily,Holidays_GX_Europe,Flat,GX,Europe/London,Eurobob Non Oxy Gasoline NWE FOB Barges,NWE,MT
GX0000004,1,Prompt,1630,2022-11-28T16:30:00,1,732.25,731.75,732,Prompt,2022-12-06T23:59:59,1,2022-11-30T00:00:00,N,,Gasoline,USD,FOB Barges,Daily,Holidays_GX_Europe,Flat,GX,Europe/London,Eurobob Non Oxy Gasoline NWE FOB Barges,NWE,MT

# All indexes published today (by London timezone) with username / password authorization: 
curl -u 'username:password' https://api.g-x.co/index?timezone=Europe/London

# All indexes published today (UTC timezone) with metadata: 
curl -u 'username:password' https://api.g-x.co/index?metadata=true

# Last 10 days data of code GX0000002: 
curl -u 'username:password' https://api.g-x.co/index?code=GX0000002&from=10d

# All Diesel indexes for last 5 days: 
curl -u 'username:password' https://api.g-x.co/index?metadata.Commodity=Diesel&from=5d

# Select specific columns - only High, Low, Mid (Code, Period, PeriodType, TimeRef always included):
curl -u 'username:password' https://api.g-x.co/index?code=GX0000004&columns.values=High,Low,Mid

# Select only metadata columns with Period wildcard:
curl -u 'username:password' https://api.g-x.co/index?code=GX0000004&metadata=true&columns.metadata=Commodity,Currency,Period*

# Authorization token passed in url
# The token used in the example was generated for user@user.com:password
curl "https://api.g-x.co/index?from=5d&token=dXNlckB1c2VyLmNvbTpwYXNzd29yZA=="

GET https://api.g-x.co/index

URL Parameters

Header Parameters

See header authentication above.

Column Selection Notes

• Required columns: The columns Code, Period, PeriodType, and TimeRef are always returned regardless of column selection parameters
• Column name matching: Column names must match exactly as they appear in the default response
• Wildcard support: Use * to select multiple columns sharing a common prefix (e.g., Period* matches Period, PeriodAbs(S), PeriodEnd(D), etc.)
• Response format compatibility: Column selection works with both CSV and JSON response formats specified via the Accept header
• Metadata dependency: The columns.metadata parameter only applies when metadata=true or metadata=only is set
• Default behavior: If no column selection parameters are provided, all available columns are returned according to the metadata parameter setting

# Select only essential price columns (required columns automatically included):
curl -u 'username:password' "https://api.g-x.co/index?code=GX0000004&columns.values=High,Low,Mid,Date(UTC)"

# Select specific metadata columns using wildcard:
curl -u 'username:password' "https://api.g-x.co/index?code=GX0000004&metadata=true&columns.metadata=Commodity,Currency,Period*"

# Combine value and metadata column selection:
curl -u 'username:password' "https://api.g-x.co/index?code=GX0000004&metadata=true&columns.values=High,Low&columns.metadata=Commodity,Currency"

# JSON response with selected fields:
curl -H 'Accept: application/json' -u 'username:password' "https://api.g-x.co/index?code=GX0000004&columns.values=High,Low,Mid"

Submit Data

Last updated: August 2026

GX accepts data submissions via file uploads to the GX data lake. File uploading has two steps

• First step is file meta data posting
• Second step is file uploading

File Metadata Posting

First step:

curl -X POST
  https://api.g-x.co/file
  -d '{
        "groupName":"group01",
        "fileName":"test.csv",
        "fileType":"SOURCE",
        "fields":[
                {
                    "name":"String field",
                    "value":"test"
                },
                {
                    "name":"Integer field",
                    "value":"1"
                },
                {
                    "name":"Float field",
                    "value":"1.1"},
                {
                    "name":"Date field",
                    "value":"2017-09-05"
                }
                ...
            ]
     }'
  -H "Authorization: ApiKey [YourGXApiKey]"

If successful, the above command returns status code 201, otherwise please check Errors section.

This endpoint stores the file metadata and returns a location to PUT the file content. If the file group requires metadata for the uploaded file, you can override default values and provide values for metadata fields that require values. On creation the call returns a 'location', you must PUT the file content to this location.

HTTP Request

POST https://api.g-x.co/file

Request Body

HTTP Response

Response:

{
    "location": "https://fileUploadURL",
    "fileId": "file id"
}

A JSON object is returned with an url to upload a file content.

File Uploading

This endpoint saves the file content into the GX Input Data Repository. You should use the 'location' link for the file from the first step response body.

Second step:

curl -X PUT --data-binary @"file-name.csv"
   "https://fileUploadURL"

If successful, the above command returns status code 200.

HTTP Request

Use --data-binary body option to select file from your local machine.

PUT https://fileUploadURL

Download PDF Reports

Last updated: August 2026

## FILES
curl "https://api.g-x.co/file/search?size=1000&from=0&query=groupName%3DProd_Reports" \
     -H 'Authorization: Bearer [yourGXAccessToken]'

The above returns a JSON response

{
  "from": 0,
  "totalSize": 100,
  "items": [
    {
      "fileName": "GX_MiddleEastCrude_Benchmark_210324.pdf",
      "fileType": "SOURCE",
      "groupName": "Prod_Reports",
      "fid": "c6da572e-d71f-4bdb-8394-a31396cf7c7a",
      "fields": {
        "SKIP_METADATA": "false"
      },
      "arrivalTime": "2021-03-24T14:47:08.399",
      "owner": "system",
      "size": 122903,
      "checkSum": "300ffa79f079f365006e9f1c85b3dcae",
      "zipped": false,
      "shared": false,
      "removed": false,
      "version": 1,
      "rootId": "c6da572e-d71f-4bdb-8394-a31396cf7c7a"
    },
    {
      "fileName": "GX_MiddleEastCrude_Benchmark_210323.pdf",
      "fileType": "SOURCE",
      "groupName": "Prod_Reports",
      "fid": "2b490176-b385-49cc-9453-bf25fe39c969",
      "fields": {
        "SKIP_METADATA": "false"
      },
      "arrivalTime": "2021-03-23T14:40:57.861",
      "owner": "system",
      "size": 134910,
      "checkSum": "2cac31e0c971600f336c69b32b399665",
      "zipped": false,
      "shared": false,
      "removed": false,
      "version": 1,
      "rootId": "2b490176-b385-49cc-9453-bf25fe39c969"
    }
  ]
}

Second step:

curl -v "https://api.g-x.co/file/c6da572e-d71f-4bdb-8394-a31396cf7c7a/download"
     -H 'Authorization: Bearer [yourGXAccessToken]'

The above returns the file as the response.

For certain Index Modules, General Index publishes PDFs on a regular (daily or weekly) basis. If you have been permissioned, reports are available using the same credentials.

There are two steps to downloading PDFs:

1. First step is retrieve file IDs
2. Second step is to retrieve the specific file based on the ID obtained.

Both steps authenticate with the Authorization header. The token URL parameter is not accepted here.

File naming

All PDFs follow the same naming convention. Files are named according to the Index Module, report type and publishing date in the following format:

GX_[Index Module]_[Report Type]_yymmdd.pdf

For example: GX_MiddleEastCrude_Benchmark_210324.pdf

The timezone of the date in the file name is according to the location of the Index Module.

Reports that are published as a correction to the original report will have the date of the original report in the filename but have a more recent arrivalTime.

Retrieve file IDs

HTTP Request

GET https://api.g-x.co/file/search

Header Parameters

URL Parameters

Retrieve specific file

The URL is in the header of the response.

HTTP Request

curl -v "https://api.g-x.co/file/[fid]/download"

Header Parameters

URL Parameters

Report Holiday Calendars

PDF reports are published daily, Monday to Friday apart from on dates specified in the relevant holiday calendar as specified below:

Please see documentation for instructions to access detailed holiday calendar information.

Errors

The General Index API uses the following status codes:

Data Integration Guide

Last updated: December 2024

Approach

The following approach is recommended to receive an accurate and timely replica of GX data.

Regular Data Pull

# All indexes published within a 15 minute time window with username / password authorization: 
"https://api.g-x.co/index?from=2022-09-01T17:00:00&to=2022-09-01T17:14:59.999&metadata=true&delta=true&token=[YourGXAccessToken]"

Query the /index api every 15 minutes with the following parameters.

HTTP Request

https://api.g-x.co/index

The range for each query should end 1 minute prior to the query time to ensure that all data in range is available via the API.

Data will be returned in UTC by default. Each series can be translated into the publication timezone using the metadata associated with the series.

Only columns updated during the insert range are returned. Where values for one or more columns have been updated during the range selected, unchanged columns will return empty values.

Metadata Request

# Metadata only
"https://api.g-x.co/index?metadata=only"

Metadata can be returned without values by passing a metadata value of 'only'.

Please note that Metadata values may be updated from time to time. Minor updates will not be included in a Data Notice.

Python SDK

Last updated: August 2026

SDK Introduction

GX maintains a Python SDK that allows developers to query and download index series data, and upload submissions to the GX data lake.

The SDK does not cover the full API surface — it wraps the commonly used features.

Installation

pip3 install generalindex

Current version, supported Python versions and the full changelog are on the PyPI project page.

Authentication

import generalindex as gx

# Option 1 - pass a token directly
api = gx.GxApi(token="[YourGXApiKey]")

# Option 2 - set once for the whole session
gx.set_token("[YourGXApiKey]")
api = gx.GxApi()

# Option 3 - environment variable NG_API_AUTHTOKEN
api = gx.GxApi()

The SDK reads credentials from environment variables, or they can be set in code.

A token can also be passed at instantiation with the token parameter, or set once for the session with gx.set_token() / gx.set_credentials(). Any handler created afterwards picks it up automatically. A token passed directly takes precedence over the environment variable.

Handlers

Documentation

Full documentation is on the PyPI project page.

Example Code

You can download an example script using the SDK.

MCP Server

Last updated: August 2026

MCP Introduction

General Index provides a remote MCP (Model Context Protocol) server that connects AI assistants — such as Claude, ChatGPT and AI-enabled developer tools — directly to GX index data. Once connected, you can ask your assistant questions in plain language and it will query GX data on your behalf.

The server URL is:

https://mcp.g-x.co/mcp

The server follows the open MCP standard, so it works with any MCP-compatible client. No advanced settings, headers or keys are required — authentication is handled by signing in with your email address.

Requesting Access

Access to the MCP server is enabled per user by General Index. Before connecting, contact GX Support or your account manager and ask for MCP access for your email address.

Your assistant will only be able to access the data your GX account is entitled to.

Signing In

When you connect for the first time, a GX sign-in page opens in your browser:

1. Enter your email address (the one enabled for MCP access).
2. A verification code is sent to that address. The code expires in 15 minutes.
3. Enter the code to complete sign-in. No password is required.

Connecting from Claude

Claude Team and Enterprise plans

An Owner or Primary Owner must first add the connector for the organisation:

1. Navigate to Organization settings > Connectors.
2. Click Add.
3. Hover over Custom, then select Web.
4. Set any name you want and enter the server URL: https://mcp.g-x.co/mcp
5. Do not specify any Advanced settings.
6. Click Add to finish.

Members can then connect:

1. Navigate to Customize > Connectors.
2. Find the connector your Owner added (it carries a "Custom" label).
3. Click Connect and complete the sign-in described above.

Claude Pro and Max plans

1. Navigate to Customize > Connectors.
2. Click + then Add custom connector.
3. Set any name you want and enter the server URL: https://mcp.g-x.co/mcp
4. Do not specify any Advanced settings.
5. Click Add, then Connect and complete the sign-in described above.

Enabling the connector in a conversation

Connectors are toggled per conversation. Click the + button at the lower left of the chat interface, then Connectors, and switch the GX connector on or off.

Connecting from Claude Code

# "gx" is the local name for the server — choose any name
claude mcp add --transport http gx https://mcp.g-x.co/mcp

Then authenticate from within Claude Code:

claude /mcp

Run the command shown, then select the GX server and follow the sign-in prompts.

Connecting from ChatGPT

Custom MCP connectors are available on ChatGPT Plus, Pro, Business, Enterprise and Education accounts.

1. In ChatGPT on the web, go to Settings > Apps (or Settings > Connectors) and enable Developer mode under Advanced settings.
2. Go to Settings > Connectors and click Add custom connector.
3. Enter the server URL: https://mcp.g-x.co/mcp
4. Choose OAuth as the connection mechanism and complete the sign-in described above.

Connecting from Microsoft Copilot

Microsoft 365 Copilot does not support adding MCP connectors directly as an end user. Instead, MCP servers are added to an agent in Microsoft Copilot Studio by someone with maker or admin access:

1. In Copilot Studio, open (or create) the agent and go to its Tools page.
2. Click Add a tool > New tool > Model Context Protocol.
3. Enter the server URL https://mcp.g-x.co/mcp and choose OAuth authentication, then follow the wizard.
4. Publish the agent to make it available to users in your organisation.

Connecting from Gemini

The consumer Gemini app does not currently support custom MCP connectors. There are two supported routes:

Gemini Enterprise (added by a team admin): go to Settings & help, select your team, then Manage team > Connected apps > Add MCP Server, and enter the server URL https://mcp.g-x.co/mcp.

# Gemini CLI: add to ~/.gemini/settings.json
{
  "mcpServers": {
    "gx": {
      "httpUrl": "https://mcp.g-x.co/mcp"
    }
  }
}

Gemini CLI (individual developers): add the server to ~/.gemini/settings.json as shown (take care to keep the JSON valid), then restart the CLI and complete sign-in when prompted.

Connecting from Other Clients

Any client that supports remote MCP servers with OAuth can connect. Enter the server URL https://mcp.g-x.co/mcp and choose OAuth as the authentication method; the client handles registration and sign-in automatically.

Available Tools

The server exposes the following tools to your assistant. Your assistant chooses which tool to use based on your question — you do not call them directly.

Data Access and Security

• The MCP server is read-only: your assistant can retrieve GX data but cannot change anything.
• The server reaches published GX index data only.
• Error messages never contain internal detail; each error carries a request ID you can quote to GX Support for investigation.
• To stop using the connector, disconnect or remove it in your client's connector settings. You can reconnect at any time by signing in again.

MCP Troubleshooting

Submitting Data

Last updated: August 2026

GX accepts data submissions from partners globally.

Source Systems

Where possible, GX has a strong preference for receiving data from formally managed IT systems (e.g. CTRM, confirmation interfaces, Bid/Offer management, nomination and logistics software) which are supported and maintained outside the Front Office. Where this is not possible (for example, with bid/offer data), this should be highlighted.

Submit Data via Email

GX accepts data submissions via a dedicated email address. Email can contain data in the email body as well as attachments. Contact GX Support for a dedicated email address to accept your data submissions.

Submit Data via API

Data is submitted to the GX data lake using the /file endpoint. This is a two-step call — POST the file metadata to https://api.g-x.co/file, then PUT the file content to the location returned.

Full detail, including the request body and the file types accepted, is in Submit Data under the API Specification.

Your API credentials must be permissioned for uploads, and GX Support will provide the groupName your submissions go to. Contact GX Support to arrange both.

Trade Data Format

Last updated: August 2026

General Index processes trade data from a number of sources across commodities and geographies. We have developed a flexible data format that allows accurate and efficient processing

GX assessment processes include both trades and bid/offer data. Our data structure applies to both.

File Format

The following describes the data format which can be used for downloading and uploading trade data as CSV files.

Trade Data Keys

The combination of keys must be unique. Transactions with the same keys will be considered corrections and the previous data will be overwritten.

All keys are required:

Columns - Core

Most Core columns are required:

Columns - Additional

Additional columns that can be accepted:

Columns - Optional volumes

For optional volumes, the following columns are accepted

Trade Metadata

Metadata must be presented in the CSV after any columns. Metadata applies to the set of keys and cannot vary by DateTime.