firestore_update_document

Modify existing document data in a Firestore collection by specifying the collection name, document ID, and updated fields.

Instructions

Update a document in a Firestore collection

Input Schema

TableJSON Schema

Name	Required	Description
`collection`	Yes	Collection name
`id`	Yes	Document ID
`data`	Yes	Updated document data

Implementation Reference

src/lib/firebase/firestoreClient.ts:155-169 (handler)

The core handler function that updates a Firestore document using the Firebase Admin SDK, handles errors, converts timestamps, and returns a formatted response with console URL.

export async function updateDocument(collection: string, id: string, data: any) {
  try {
    if (!db) {
      return { content: [{ type: 'text', text: 'Firebase is not initialized. SERVICE_ACCOUNT_KEY_PATH environment variable is required.' }], isError: true };
    }
    
    await db.collection(collection).doc(id).update(data);
    const projectId = getProjectId();
    convertTimestampsToISO(data);
    const consoleUrl = `https://console.firebase.google.com/project/${projectId}/firestore/data/${collection}/${id}`;
    return { content: [{ type: 'text', text: JSON.stringify({ id, url: consoleUrl, document: data }) }] };
  } catch (error) {
    return { content: [{ type: 'text', text: `Error updating document: ${(error as Error).message}` }], isError: true };
  }
}

src/index.ts:141-162 (registration)

Tool registration in the listTools response, including name, description, and input schema.

{
  name: 'firestore_update_document',
  description: 'Update a document in a Firestore collection',
  inputSchema: {
    type: 'object',
    properties: {
      collection: {
        type: 'string',
        description: 'Collection name'
      },
      id: {
        type: 'string',
        description: 'Document ID'
      },
      data: {
        type: 'object',
        description: 'Updated document data'
      }
    },
    required: ['collection', 'id', 'data']
  }
},

src/index.ts:240-241 (registration)
Dispatch in the CallToolRequest handler switch statement that routes to the updateDocument implementation.
```
case 'firestore_update_document':
  return updateDocument(args.collection as string, args.id as string, args.data as object);
```

src/lib/firebase/firestoreClient.ts:51-58 (helper)

Helper function used in updateDocument (and others) to convert Firestore Timestamp objects to ISO strings for JSON serialization.

function convertTimestampsToISO(data: any) {
  for (const key in data) {
    if (data[key] instanceof Timestamp) {
      data[key] = data[key].toDate().toISOString();
    }
  }
  return data;
}

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