FlowiseAI/Flowise · error · Error

Graph API Error ${response.status}: ${response.statusText} -

Error message

Graph API Error ${response.status}: ${response.statusText} - ${errorText}

What it means

Thrown by OutlookAPI.makeGraphRequest when the fetch to Microsoft Graph returns a non-OK HTTP status. The message includes status code, statusText, and the raw response body (errorText) so the caller can see Graph's own error JSON. The request always sends Authorization: Bearer <accessToken> and JSON content type.

Source

Thrown at packages/components/nodes/tools/MicrosoftOutlook/core.ts:158

        this.accessToken = args.accessToken ?? ''
    }

    async makeGraphRequest(url: string, method: string = 'GET', body?: any, params?: any): Promise<string> {
        const headers = {
            Authorization: `Bearer ${this.accessToken}`,
            'Content-Type': 'application/json',
            ...this.headers
        }

        const response = await fetch(url, {
            method,
            headers,
            body: body ? JSON.stringify(body) : undefined
        })

        if (!response.ok) {
            const errorText = await response.text()
            throw new Error(`Graph API Error ${response.status}: ${response.statusText} - ${errorText}`)
        }

        const data = await response.text()
        return data + TOOL_ARGS_PREFIX + JSON.stringify(params)
    }

    parseEmailAddresses(emailString: string) {
        return emailString.split(',').map((email) => ({
            emailAddress: {
                address: email.trim(),
                name: email.trim()
            }
        }))
    }
}

// Calendar Tools
class ListCalendarsTool extends BaseOutlookTool {

View on GitHub (pinned to abe4a8601a)

Solutions

1. Inspect status: 401 -> ensure refreshOAuth2Token ran and the credential has a refresh_token; 403 -> add the required Graph permission scopes and re-consent; 404 -> verify the resource id; 429 -> honor Retry-After.
2. Surface errorText to identify Graph's specific error code (e.g. 'code': 'InvalidAuthenticationToken').
3. For 5xx, retry with backoff; for persistent failures check the Microsoft 365 service health.

Example fix

// before
const data = await outlook.makeGraphRequest(url, 'POST', body)

// after: handle 401 by refreshing and retrying once
try {
  return await outlook.makeGraphRequest(url, 'POST', body)
} catch (e) {
  if (/Graph API Error 401/.test(e.message)) {
    await refreshOAuth2Token(credId, credData, options)
    return await outlook.makeGraphRequest(url, 'POST', body)
  }
  throw e
}

// Pre-flight: confirm token present and scopes likely sufficient before the call.
if (!accessToken) throw new Error('No access token')
// Best-effort URL/method validation before fetch
if (!url.startsWith('https://graph.microsoft.com/')) throw new Error('URL must target Graph')

const isGraphError = (e: unknown): boolean =>
  e instanceof Error && /^Graph API Error \d{3}:/.test(e.message)

try {
  return await outlook.makeGraphRequest(url, method, body, params)
} catch (e) {
  if (/Graph API Error 401/.test(e.message)) {
    await refreshOAuth2Token(credId, credData, options)
    return await outlook.makeGraphRequest(url, method, body, params) // one retry
  }
  if (/Graph API Error 429/.test(e.message)) {
    // honor Retry-After, then retry
  }
  throw e
}

When it happens

Trigger: Any Graph call (calendar/message actions) where response.ok is false: 401 (expired/invalid token), 403 (insufficient scopes), 404 (resource not found), 429 (throttled), 5xx (Graph outage), or 400 (malformed body/URL).

Common situations: Access token expired (401) — refresh cycle not running; missing Microsoft Graph scopes such as Calendars.ReadWrite or Mail.Send (403); invalid event/message id (404); throttling during bulk operations (429).

Related errors

• ${errorMessage}
• HTTP error! status: ${response.status}
• Failed to fetch ${url}: ${error}
• Failed to post ${url}: ${error}
• Azure Rerank API call failed: ${error.message}

AI-assisted analysis of FlowiseAI/Flowise@abe4a8601a (2026-08-12). Data as JSON: /api/errors/e7072398f17e21e8. Report an issue: GitHub.