FlowiseAI/Flowise · error · Error

Failed to retrieve access token: Response missing access_tok

Error message

Failed to retrieve access token: Response missing access_token field

What it means

Thrown by PipedreamMCP.fetchAccessToken after the OAuth token exchange to https://api.pipedream.com/v1/oauth/token succeeds (HTTP 200) but the response body has no access_token field. The client-credentials grant returned a payload that is missing the expected token, so the code cannot proceed to cache or use a token.

Source

Thrown at packages/components/nodes/tools/MCP/Pipedream/PipedreamMCP.ts:220

        try {
            const body: Record<string, string> = {
                grant_type: 'client_credentials',
                client_id: clientId,
                client_secret: clientSecret
            }
            if (scope) {
                body.scope = scope
            }
            const response = await axios.post('https://api.pipedream.com/v1/oauth/token', body, {
                headers: {
                    'Content-Type': 'application/json'
                }
            })

            const accessToken = response.data?.access_token
            if (!accessToken) {
                throw new Error('Failed to retrieve access token: Response missing access_token field')
            }

            const expiresIn = response.data?.expires_in ?? 3600
            tokenCache.set(tokenCacheKey, {
                token: accessToken,
                expiresAt: Date.now() + expiresIn * 1000
            })

            return accessToken
        } catch (error: any) {
            if (error.response?.status === 401) {
                tokenCache.delete(tokenCacheKey)
                throw new Error('Invalid Pipedream credentials. Please verify your Client ID and Client Secret.')
            }
            const message = error.message ?? 'Unknown error'
            const code = error.code ?? error.response?.status ?? 'UNKNOWN'
            throw new Error(`Pipedream OAuth token request failed [${code}]: ${message}`)
        }

View on GitHub (pinned to abe4a8601a)

Solutions

Log response.status and response.data to confirm what Pipedream actually returned.
Check Pipedream status/changelog for a token-endpoint response format change.
Ensure no proxy is rewriting the response body; call the endpoint directly to compare.
If the body shape changed, update the access_token extraction path in fetchAccessToken accordingly.

Example fix

// before
const accessToken = response.data?.access_token
if (!accessToken) {
    throw new Error('Failed to retrieve access token: Response missing access_token field')
}
// after (diagnostic, then fix extraction if shape changed)
console.error('Pipedream token response:', response.status, JSON.stringify(response.data))
const accessToken = response.data?.access_token || response.data?.token
if (!accessToken) {
    throw new Error('Failed to retrieve access token: Response missing access_token field')
}

Defensive patterns

Strategy: try-catch

Type guard

function hasAccessTokenField(data: unknown): boolean {
    return typeof data === 'object' && data !== null
        && typeof (data as any).access_token === 'string'
        && (data as any).access_token.length > 0
}

Try / catch

try {
    const token = await pipedream.fetchAccessToken(clientId, clientSecret, scope)
} catch (e) {
    if (e instanceof Error && e.message.startsWith('Failed to retrieve access token')) {
        // log response shape, alert ops; this is an upstream contract issue, not a user fix
    }
}

Prevention

Pin/monitor the Pipedream API contract; add an integration test that asserts access_token is present.
Log response.status with response.data on failure to speed diagnosis.
Treat this error as a candidate incident rather than a user-config problem.

When it happens

Trigger: A successful POST to Pipedream's /v1/oauth/token where response.data is null/undefined, an unexpected JSON shape, or response.data.access_token is empty string — for example an upstream API contract change, a proxy returning an HTML error page with 200, or a malformed response.

Common situations: Pipedream API changes its token response schema; an intermediary (corporate proxy, gateway) returns a 200 with a non-JSON body; axios transforms the response unexpectedly; the endpoint returns a partial object under load.

Related errors

AI-assisted analysis of FlowiseAI/Flowise@abe4a8601a (2026-08-12). Data as JSON: /api/errors/115b79066be8fc05. Report an issue: GitHub.