mem0ai/mem0 · error · Error

Mem0 API key cannot be empty

Error message

Mem0 API key cannot be empty

What it means

The third branch of _validateApiKey() rejects strings that are empty after trimming — values like '', ' ', or '\t'. This catches half-configured keys (placeholder strings, whitespace from copy-paste) that would otherwise send a syntactically present but useless Authorization header.

Source

Thrown at mem0-ts/src/client/mem0.ts:117

  apiKey: string;
  host: string;
  private organizationId: string | number | null;
  private projectId: string | number | null;
  headers: Record<string, string>;
  client: any;
  telemetryId: string;
  private initialized: Promise<void>;
  private identityCacheMax: number;

  _validateApiKey(): any {
    if (!this.apiKey) {
      throw new Error("Mem0 API key is required");
    }
    if (typeof this.apiKey !== "string") {
      throw new Error("Mem0 API key must be a string");
    }
    if (this.apiKey.trim() === "") {
      throw new Error("Mem0 API key cannot be empty");
    }
  }

  constructor(options: ClientOptions) {
    this.apiKey = options.apiKey;
    this.host = options.host || "https://api.mem0.ai";
    this.organizationId = null;
    this.projectId = null;
    this.identityCacheMax =
      options.identityCacheMax ?? IDENTITY_CACHE_MAX_DEFAULT;

    this.headers = {
      Authorization: `Token ${this.apiKey}`,
      "Content-Type": "application/json",
    };

    this.client = axios.create({
      baseURL: this.host,

View on GitHub (pinned to 001c235229)

Solutions

1. Set a real key: MEM0_API_KEY=m0-... in your .env / secret store.
2. Trim on your side at startup: new MemoryClient({ apiKey: process.env.MEM0_API_KEY?.trim() }).
3. Remove placeholder/space-only entries from .env templates that get copied into real environments.

Example fix

# before
MEM0_API_KEY=

# after
MEM0_API_KEY=m0-your-real-key

const cleanApiKey = (v: string | undefined): string => {
  const t = (v ?? '').trim();
  if (t.length === 0) throw new Error('MEM0_API_KEY is blank — set a real key in the environment');
  return t;
};

new MemoryClient({ apiKey: cleanApiKey(process.env.MEM0_API_KEY) });

const isNonBlankString = (v: unknown): v is string =>
  typeof v === 'string' && v.trim().length > 0;

When it happens

Trigger: Constructing the client with apiKey: ' ' or apiKey: '' — typically from a .env entry with no value (MEM0_API_KEY=) or a placeholder like spaces; dotenv parses MEM0_API_KEY= as empty string, which passes the falsy check for ''? No — '' is falsy so it hits 'required'; ' ' (spaces) is truthy and reaches this branch.

Common situations: Template .env files committed with blank values; keys pasted with trailing whitespace/newlines; CI secrets defined but empty.

Related errors

• Mem0 API key is required
• Provide text or metadata to update
• Mem0 API key must be a string
• organizationId and projectId must be set to access instructi
• apiKey is required for Mem0Memory

AI-assisted analysis of mem0ai/mem0@001c235229 (2026-08-15). Data as JSON: /api/errors/e4fd82d105ed3808. Report an issue: GitHub.