NousResearch/hermes-agent · warning · Error

Bearer token required

Error message

Bearer token required

What it means

When an HTTP-transport MCP server selects header auth (httpAuth === 'header'), a bearer token is mandatory and is sent as bearer_token in the create payload. A whitespace-only token fails the trim check and throws client-side.

Source

Thrown at web/src/lib/mcp-server-create.ts:58

    if (!line) continue;
    const separator = line.indexOf("=");
    if (separator === -1) continue;
    const key = line.slice(0, separator).trim();
    const value = line.slice(separator + 1).trim();
    if (key) env[key] = value;
  }
  return env;
}

export function buildMcpServerCreate(draft: McpServerDraft): McpServerCreate {
  const name = draft.name.trim();
  if (!name) throw new Error("Name required");

  if (draft.transport === "http") {
    const url = draft.url.trim();
    if (!url) throw new Error("URL required");
    if (draft.httpAuth === "header" && !draft.bearerToken.trim()) {
      throw new Error("Bearer token required");
    }

    const server: McpServerCreate = { name, url };
    if (draft.httpAuth !== "none") server.auth = draft.httpAuth;
    if (draft.httpAuth === "header") {
      server.bearer_token = draft.bearerToken;
    }
    return server;
  }

  const command = draft.command.trim();
  if (!command) throw new Error("Command required");

  const server: McpServerCreate = { name, command };
  const args = parseArgs(draft.args);
  if (args.length) server.args = args;
  const env = parseEnv(draft.env);
  if (Object.keys(env).length) server.env = env;

View on GitHub (pinned to c896c09c42)

Solutions

1. Paste the server's bearer token into the token field and submit.
2. If the server needs no auth header, set auth to 'none'; if it uses OAuth, pick that option instead.
3. Disable submit until bearerToken.trim() is non-empty when httpAuth === 'header'.

if (draft.transport === 'http' && draft.httpAuth === 'header' && !draft.bearerToken.trim()) {
  setFieldError('bearerToken', 'Bearer token is required for header auth')
  return
}

function hasBearerWhenHeader(d: McpServerDraft): boolean {
  return d.httpAuth !== 'header' || d.bearerToken.trim().length > 0
}

try {
  const payload = buildMcpServerCreate(draft)
} catch (err) {
  if (String(err) === 'Bearer token required') { focusField('bearerToken'); return }
  throw err
}

When it happens

Trigger: Choosing 'Bearer token' auth in the add-server form but leaving the token field empty; pasting only whitespace; state where httpAuth defaults to 'header' before the user enters a token.

Common situations: Users selecting header auth 'just in case' without a token; autofill failing on password-type inputs; form resubmission after a failed attempt clearing the token field.

Related errors

• Name required
• URL required
• Command required
• Remote gateway session token is required.
• Preview mode — launching is disabled.

AI-assisted analysis of NousResearch/hermes-agent@c896c09c42 (2026-08-14). Data as JSON: /api/errors/737a567b1ea938ef. Report an issue: GitHub.