What causes "MCP server with id ${id} not found" in mastra-ai/mastra?

Verify the server exists (get/list) before updating.

MCP server with id not found

Error message

MCP server with id ${id} not found

What it means

Thrown by `update` in the in-memory MCP servers domain when no MCP server with the given id is stored. Updates mutate only existing records and will not create one implicitly.

Solutions

Verify the server exists (get/list) before updating.
Implement upsert: fall back to create when update reports not-found.
Share one storage instance across the code path performing create and update.

Example fix

// before
await mcpServers.update({ id: serverId, status: 'active' });
// after
try {
  await mcpServers.update({ id: serverId, status: 'active' });
} catch (e) {
  if (!/not found/.test(String(e))) throw e;
  await mcpServers.create({ mcpServer: { id: serverId } });
}

Defensive patterns

Strategy: try-catch

Validate before calling

const existing = await mcpServers.get(id);
if (!existing) throw new Error(`Cannot update: MCP server ${id} does not exist`);

Try / catch

try {
  await mcpServers.update({ id, ...updates });
} catch (err) {
  if (err instanceof Error && /not found/.test(err.message)) {
    // surface 404 or create the record
    return;
  }
  throw err;
}

Prevention

Look up ids via get/list before updating.
Wrap server mutations in an upsert helper.
Keep create/update flows on the same storage instance.

When it happens

Trigger: Calling `storage.mcpServers.update({ id, ...updates })` with an id absent from the map — never created, created in a different storage instance, or already deleted.

Common situations: Stale references after storage re-instantiation between tests; ids from another environment; typos or changed id schemes.

Understand the failure class

Background: 'Could not be found', 'does not exist', 'not found in database': the resource-not-found family when an ID, slug, key, or URI lookup comes back empty — this error's family across 20 libraries.

Related errors

AI-assisted analysis of mastra-ai/mastra@75dd419e61 (2026-08-30). Data as JSON: /api/errors/f27cb672489a6f49. Report an issue: GitHub.

Appendix: source

Thrown at packages/core/src/storage/domains/mcp-servers/inmemory.ts:88

    await this.createVersion({
      id: versionId,
      mcpServerId: mcpServer.id,
      versionNumber: 1,
      ...snapshotConfig,
      changedFields: Object.keys(snapshotConfig),
      changeMessage: 'Initial version',
    });

    // Return the thin record
    return this.deepCopyConfig(newConfig);
  }

  async update(input: StorageUpdateMCPServerInput): Promise<StorageMCPServerType> {
    const { id, ...updates } = input;

    const existingConfig = this.db.mcpServers.get(id);
    if (!existingConfig) {
      throw new Error(`MCP server with id ${id} not found`);
    }

    // Separate metadata fields from config fields
    const { authorId, activeVersionId, metadata, status } = updates;

    // Update metadata fields on the record
    const updatedConfig: StorageMCPServerType = {
      ...existingConfig,
      ...(authorId !== undefined && { authorId }),
      ...(activeVersionId !== undefined && { activeVersionId }),
      ...(status !== undefined && { status: status as StorageMCPServerType['status'] }),
      ...(metadata !== undefined && {
        metadata: { ...existingConfig.metadata, ...metadata },
      }),
      updatedAt: new Date(),
    };

    // Save the updated record

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