Connect the Claude app to Narwhal

Q: How do I give the Claude app my Narwhal API key?

Choose No sign-in and add authorization under Request headers with the value Bearer YOUR_KEY. Claude sends that exact value, so include the word Bearer and a space before the key.

The Claude app can connect to Narwhal when your organization has Request headers, a beta available to a limited set of organizations. Choose No sign-in and add the API key as an authorization header. If Request headers is missing from the Add custom connector dialog, use [Claude Code](/agents/claude) instead, because Narwhal has no OAuth sign-in for MCP.

Quick start

Get a free Narwhal key from https://narwhalapi.com/signup and keep it out of prompts and URLs.
In Claude web or Desktop, open Customize, Connectors and Add custom connector.
Enter the exact MCP URL, choose No sign-in and find Request headers.
Add authorization with the value Bearer YOUR_KEY, including the word Bearer and a space, then save.
In the chat, select the plus button and turn on Narwhal under Connectors.

MCP configuration

The connector needs the HTTPS server URL, No sign-in authentication and an authorization request header. Claude sends the header value exactly as typed and adds no prefix, so include Bearer and a space before your key.

Add custom connector

MCP server URL:  https://api.narwhalapi.com/mcp
Authentication:  No sign-in
Request header:  authorization
Header value:    Bearer YOUR_NARWHAL_API_KEY
Required:        yes

Claude stores header values securely and does not display them again after saving. Authentication settings cannot be edited later; remove the connector and add it again if you need to change them.

Tools you get

The Claude app gets every read-only tool group through one connection when the connector is enabled. Discovery and initialization are free, and each successful call uses one request shared with REST.

Group	What you can ask for	Tools
Economic indicators	Ask for CPI, inflation, unemployment, labour force participation, GDP, GDP growth and trade by country; coverage differs by indicator.	`economics_get_cpi` `economics_get_inflation` `economics_get_unemployment` `economics_get_labour_force_participation` `economics_get_gdp` `economics_get_gdp_growth` `economics_get_trade` `economics_get_cpi_history` `economics_get_inflation_history` `economics_get_unemployment_history` `economics_get_labour_force_participation_history` `economics_get_gdp_history` `economics_get_gdp_growth_history` `economics_get_trade_history` `economics_read_series_observations`
Currency rates	Ask for current exchange rates, historical rates, currency conversions and rate bars for a currency pair.	`fx_get_rates` `fx_get_rate_history` `fx_convert_currency` `fx_get_rate_bars`
Commodity prices	Ask for spot prices for gold, silver, platinum, palladium, copper, WTI crude oil, and Brent crude oil, their price history, and physical palm oil prices (crude palm oil and fresh fruit bunches).	`commodities_get_spot_price` `commodities_get_price_history` `commodities_list_palmoil_physical_series` `commodities_get_palmoil_physical_price` `commodities_get_palmoil_physical_observations` `commodities_list_physical_series` `commodities_get_physical_series` `commodities_get_physical_latest` `commodities_get_physical_observations`
Releases and events	Ask for official economic release dates and event details before you plan a country briefing.	`economics_list_releases` `economics_get_release` `events_list` `events_get`
Public holidays	Ask for public holidays by country, holidays on a particular date or the next holiday.	`calendars_list_holidays` `calendars_get_holidays_on_date` `calendars_get_next_holiday`
Prediction market odds	Ask for prediction market topics and events with scalar, extreme, timing and binary outcomes, their history, and policy paths by authority.	`predictions_list_topics` `predictions_get_topic` `predictions_list_events` `predictions_get_scalar` `predictions_get_extreme` `predictions_get_timing` `predictions_get_binary` `predictions_get_scalar_history` `predictions_get_extreme_history` `predictions_get_timing_history` `predictions_get_binary_history` `predictions_get_policy_path` `predictions_get_policy_path_history`
Government bond yields	Ask for government bond yield curves for the US, the UK, Germany, Japan, and Canada through the same Narwhal connection.	`economics_get_yield_curve` `economics_get_yield_curve_history`

Example prompts

Get the latest CPI value for Canada.
Show the current GBP/USD exchange rate.
Get the available palm oil price history.
Find the next official CPI release date for the United States.
List the public holidays in Japan for the current year.

Common workflows

Prepare a Canadian CPI briefing

Canadian CPI comes from economics_get_cpi with Canada selected. It returns the latest headline index value and its index base.

Check a currency pair during chat

Convert your GBP amount to USD with fx_convert_currency, supplying the amount and both currencies for a conversion at the current indicative rate.

Review palm oil observations with Claude

Get palm oil price history. Find a series with commodities_list_palmoil_physical_series, then pass its series ID to commodities_get_palmoil_physical_observations for observations by native period.

Plan around the next CPI release

When is the next United States CPI release? Use economics_list_releases with the United States and a date window of up to 366 days to find the scheduled date.

Tips

On Team and Enterprise, an Owner adds the connector under Organization settings, Connectors, Add, Custom; members then connect with their own account.
The Claude Free plan can add one custom connector, and you must still have access to Request headers to authenticate Narwhal.
Use the standard header name authorization; Anthropic approves custom header names and allows up to four headers.
Requests come from Anthropic's cloud, so the server URL must be public HTTPS; Narwhal's hosted endpoint meets that requirement.

FAQ

How do I give the Claude app my Narwhal API key?

Choose No sign-in and add authorization under Request headers with the value Bearer YOUR_KEY. Claude sends that exact value, so include the word Bearer and a space before the key.

Why is Request headers missing from my Claude connector dialog?

Your organization does not have access to that beta yet. Use Claude Code with a Bearer key instead; Narwhal has no OAuth sign-in for MCP that you can select as an alternative.

Can I change the saved authentication settings in Claude?

No, authentication settings cannot be changed after saving, so remove the connector and add it again. Claude stores header values securely and does not show the saved value again.

Troubleshooting

Symptom	Check
Narwhal does not show in the chat	Open the plus button in that chat, select Connectors and turn Narwhal on. On Team or Enterprise, check that an Owner added the connector.
The connector returns `401 invalid_api_key`	Check the key is active and the header value includes `Bearer` plus a space. Recreate the connector to change saved authentication settings.
The dialog has no Request headers section	The organization lacks access to this beta. Use Claude Code to connect with the same Narwhal key.
The connector cannot reach the server	Use exactly https://api.narwhalapi.com/mcp without a trailing slash; the URL must be reachable from Anthropic's cloud.