Response body from fetch not successfully parsing to JSON, even though it's verifiably valid JSON

Question

I'm trying to fetch some data from a webservice like so:

async function request(path: string, args: RequestInit | undefined): Promise<Response> {
    const headers: RequestInit = {
        mode: "no-cors" as RequestMode,
        headers: {
            'Content-Type': 'application/json'
        }
    };

    const url = `${ROOT_URL}/${path}?apiKey=${API_KEY}`
    const options = {
        ...args,
        ...headers,
    }

    const result = await fetch(url, options)
    return result;
}

try {

    const response = await request('my/endpoint', {
        method: 'GET',
    })

    console.log('received response: ')
    console.log(response)

    const result = await response.json();
    console.log(result)
    return Promise.resolve(result)

} catch(error) {

    console.log('error:')
    console.log(error)
    return Promise.reject(error)

}

When sending this request, I see the following error in the console:

[Log] SyntaxError: The string did not match the expected pattern. — imagesSlice.ts:110 (bundle.js, line 633)

Additionally, the body field of the response object is null.

However, if I curl the exact URL, or paste it into the browser, the response body contains the correct JSON, which is verifiable by jsonlint.

What could be failing here? And also how can I debug this?

I have tried using await response.text() to take a look at the response body, and this returns an empty string.