Integration · Developer tools

Connect Claude & ChatGPT to Letta

Work with your Letta agents from the AI assistant you already use. Ask it what an agent remembers, change its persona or system prompt, attach a tool, or send the agent a message and read the reply. It can also browse conversations, message history, runs, folders and the models available to your agents.

Connect Letta free

Free plan, no credit card. Takes about a minute.

Try asking

“What does my support agent have in its human memory block?”
The AI finds the agent and reads its human core memory block.
“Search the research agent's archival memory for anything about pricing.”
It searches the agent's archival memory by meaning and returns the closest passages.
“Attach the web search tool to my support agent.”
It finds the tool ID in your account and attaches it to the agent.

What your AI can do

Agents and memory

List and read agents, update their name, system prompt, model and tags, and read or replace core memory blocks such as persona and human.

Archival memory

List, search, add and delete passages in an agent's long-term archival memory.

Messages, tools and runs

Send messages to agents or conversations, read message history, attach and detach tools, and check runs, folders and models.

“Ask the onboarding agent to summarize what it knows about Acme.”
It sends the message to the agent and returns its reply. The agent may call its own tools and update its memory while answering.
“Switch the triage agent to a different model.”
It lists the available models, then updates the agent with the one you pick.
“Did the agent's last run finish, and why did it stop?”
It lists the agent's runs and reads the status and stop reason of the latest one.

170 tools for Letta

These tools are switched on when you connect. You can switch any of them off, or require your approval before it runs.

add_archival_memoryChanges dataSave a passage to an agent's long-term archival memory: pass `agent_id` and `text`, optionally `tags`.
attach_toolChanges dataAttach a tool to an agent by `agent_id` and `tool_id` (tool-...), so the agent can use it.
cancel_batchMoves moneyCancel a batch (batch id). Financial or irreversible action; may require approval. API summary: Cancel Batch.
cancel_conversationDeletesCancel a message (conversation id). Destructive action; may require approval. API summary: Cancel Conversation.
cancel_messageDeletesCancel a message (agent id). Destructive action; may require approval. API summary: Cancel Message.
cancel_projectDeletesCancel a project (job id). Destructive action; may require approval. API summary: Cancel Job.
create_agentChanges dataCreate a new agent. Required: body. Search agents first to avoid duplicates. API summary: Create Agent.
create_agent_generateChanges dataCreate a new generate for a agent. Required: prompt. API summary: Generate Completion.
create_agent_recompileChanges dataCreate a new recompile for a agent. API summary: Recompile Agent.
create_agent_scheduleVisible to othersCreate a new schedule for a agent. Required: messages or schedule. Has effects visible outside this system. API summary: Schedule Agent Message.
create_agent_summarizeChanges dataCreate a new summarize for a agent. API summary: Summarize Messages.
create_agents_from_templateChanges dataCreate a new agent for a template. Search agents first to avoid duplicates. API summary: Create Agents From Template.
create_archiveChanges dataCreate a new archive. Required: name. Search archives first to avoid duplicates. API summary: Create Archive.
create_archive_passageChanges dataCreate a new passage for a archive. Required: text. Search passages first to avoid duplicates. API summary: Create Passage In Archive.
create_asyncVisible to othersCreate a new async. Has effects visible outside this system. API summary: Create Message Async.
create_batchVisible to othersCreate a new batch. Required: passages. Has effects visible outside this system. API summary: Create Passages In Archive.
create_batch_create_batchVisible to othersCreate a new batch. Required: requests. Has effects visible outside this system. API summary: Create Batch.
create_blockChanges dataCreate a new block. Required: value or label. Search blocks first to avoid duplicates. API summary: Create Block.
create_bulk_delete_inactiveVisible to othersCreate a new bulk delete inactive. Required: inactive before. Has effects visible outside this system. API summary: Bulk Soft-Delete Inactive Agents.
create_connectChanges dataCreate a new connect. Required: body. API summary: Connect Mcp Server.
create_conversationChanges dataStart a new conversation with an agent by `agent_id`, optionally with a `summary`. Use send_conversation_message to talk in it.
create_deployment_migrateChanges dataCreate a new migrate for a deployment. Required: version. API summary: Migrate deployment to template version (Cloud-only).
create_folderChanges dataCreate a new folder. Required: name. Search folders first to avoid duplicates. API summary: Create Folder.
create_mcp_serverChanges dataCreate a new mcp server. Required: server name or config. API summary: Create Mcp Server.
create_message_compactChanges dataCreate a new compact for a message. API summary: Compact Conversation.
create_message_fork_conversationChanges dataCreate a new message for a message. Search messages first to avoid duplicates. API summary: Fork Conversation.
create_message_recompileChanges dataCreate a new recompile for a message. API summary: Recompile Conversation.
create_message_streamChanges dataCreate a new stream for a message. API summary: Retrieve Conversation Stream.
create_runChanges dataCreate a new run. Required: source code or args. API summary: Run Tool From Source.
create_run_streamChanges dataCreate a new stream for a run. API summary: Retrieve Stream For Run.
create_server_resyncChanges dataCreate a new resync for a server. API summary: Resync Mcp Server Tools.
create_templateChanges dataCreate a new template. Search templates first to avoid duplicates. API summary: Create template (Cloud-only).
create_template_agentChanges dataCreate a new agent for a template. Search agents first to avoid duplicates. API summary: Create Agents From Template.
create_template_cloud_onlyChanges dataUpdate an existing template identified by project id. API summary: Create template (Cloud-only).
create_template_forkChanges dataCreate a new fork for a template. API summary: Fork template (Cloud-only).
create_template_rollbackChanges dataCreate a new rollback for a template. Required: version. API summary: Rollback template to previous version (Cloud-only).
create_template_rollback_templates_rollback_templateChanges dataCreate a new rollback for a template. Required: version. API summary: Rollback template to previous version (Cloud-only).
create_template_saveChanges dataCreate a new save for a template. API summary: Save template version (Cloud-only).
create_testChanges dataCreate a new test. Required: body. API summary: Test Mcp Server.
create_toolChanges dataCreate a new tool. Required: source code. Search tools first to avoid duplicates. API summary: Create Tool.
create_tool_base_toolsChanges dataCreate a new tool. Search tools first to avoid duplicates. API summary: Upsert Base Tools.
create_tool_executeChanges dataCreate a new execute for a tool. API summary: Execute Mcp Tool.
create_tool_runChanges dataCreate a new run for a tool. API summary: Run Tool For Agent.
delete_agentDeletesPermanently delete a agent by agent id. Destructive action; may require approval. API summary: Delete Agent.
delete_agent_scheduleDeletesPermanently delete a schedule by scheduled message id. Destructive action; may require approval. API summary: Delete Scheduled Agent Message.
delete_archival_memoryDeletesPermanently delete one passage from an agent's archival memory by `agent_id` and `memory_id`. This cannot be undone.
delete_archiveDeletesPermanently delete a archive by archive id. Destructive action; may require approval. API summary: Delete Archive.
delete_archive_passageDeletesPermanently delete a passage by passage id. Destructive action; may require approval. API summary: Delete Passage From Archive.
delete_blockDeletesPermanently delete a block by block id. Destructive action; may require approval. API summary: Delete Block.
delete_file_from_folderDeletesPermanently delete a folder by file id. Destructive action; may require approval. API summary: Delete File From Folder.
delete_folderDeletesPermanently delete a folder by folder id. Destructive action; may require approval. API summary: Delete Folder.
delete_mcp_serverDeletesPermanently delete a mcp server by mcp server id. Destructive action; may require approval. API summary: Delete Mcp Server.
delete_messageDeletesPermanently delete a message by message id. Destructive action; may require approval. API summary: Delete Conversation.
delete_projectDeletesPermanently delete a project by project id. Destructive action; may require approval. API summary: Delete Job.
delete_runDeletesPermanently delete a run by run id. Destructive action; may require approval. API summary: Delete Run.
delete_serverDeletesPermanently delete a server by mcp server name. Destructive action; may require approval. API summary: Delete Mcp Server From Config.
delete_templateDeletesPermanently delete a template by template name. Destructive action; may require approval. API summary: Delete template (Cloud-only).
delete_template_cloud_onlyDeletesPermanently delete a template by template name. Destructive action; may require approval. API summary: Delete template (Cloud-only).
delete_toolDeletesPermanently delete a tool by tool id. Destructive action; may require approval. API summary: Delete Tool.
detach_toolChanges dataRemove a tool from an agent by `agent_id` and `tool_id`. The tool itself is kept.
export_agent_with_skillsChanges dataExport agents. API summary: Export Agent With Skills.
export_agentsExport agents.
get_agentGet one agent by `agent_id` (agent-...), with its model, system prompt, tools and memory blocks.
get_agent_2Get one agent. API summary: Count Agents.
get_agent_scheduleGet one schedule for a agent by scheduled message id. API summary: Retrieve Scheduled Agent Message.
get_archiveGet one archive by archive id. API summary: Retrieve Archive.
get_batchGet one batch by batch id. API summary: Retrieve Batch.
get_block_countGet one block. API summary: Count Blocks.
get_connectGet one connect by mcp server id. API summary: Connect Mcp Server.
get_folderGet one folder. API summary: Count Folders.
get_folder_documentGet one document for a folder by document id. API summary: Retrieve File.
get_mcp_serverGet one mcp server by mcp server id. API summary: Retrieve Mcp Server.
get_mcp_server_toolGet one tool for a mcp server by tool id. API summary: Retrieve Mcp Tool.
get_memory_blockGet one core memory block of an agent by `agent_id` and `block_label` (for example human or persona).
get_messageGet one message by message id. API summary: Retrieve Conversation.
get_projectGet one project by project id. API summary: Retrieve Job.
get_runGet one run by `run_id`, with its status and stop reason.
get_searchGet one search. API summary: Count Deployed Agents.
get_stepGet one step by step id. API summary: Retrieve Step.
get_toolGet one tool by tool id. API summary: Retrieve Tool.
get_tool_countGet one tool. API summary: Count Tools.
list_agent_documentsList documents for a agent. Optional filters: before, order, order by or is open. Results are paginated. API summary: List Files For Agent.
list_agent_foldersList folders for a agent. Optional filters: before, order or order by. Results are paginated. API summary: List Folders For Agent.
list_agent_groupsList groups for a agent. Optional filters: manager type, before, order or order by. Results are paginated. API summary: List Groups For Agent.
list_agent_messagesList the message history of an agent by `agent_id`, optionally filtered by `conversation_id`.
list_agent_profile_picturesList profile pictures for a agent. API summary: Get Agent Profile Picture.
list_agent_schedulesList schedules for a agent. Results are paginated. API summary: List Scheduled Agent Messages.
list_agent_toolsList the tools attached to an agent by `agent_id`.
list_agentsList agents, optionally filtered by `name`, `query_text`, `tags` or `project_id`. Use this to find an agent ID before other calls.
list_all_messagesList messages. Optional filters: before, order, conversation id or include return message types. Results are paginated. API summary: List All Messages.
list_archival_memoriesList passages in an agent's long-term archival memory by `agent_id`, optionally filtered by text with `search`.
list_archive_agentsList agents for a archive. Optional filters: before or order. Results are paginated. API summary: List Agents For Archive.
list_batch_messagesList messages for a batch. Optional filters: before, order, order by or agent id. Results are paginated. API summary: List Messages For Batch.
list_batchesList batches. Optional filters: before, order or order by. Results are paginated.
list_block_agentsList agents for a block. Optional filters: before, order or order by. Results are paginated. API summary: List Agents For Block.
list_callbacksList callbacks. Optional filters: code, state, error or error description. API summary: Mcp Oauth Callback.
list_contentsList contents. Optional filters: file path or ref. API summary: Read File Content.
list_conversation_messagesList the messages in one conversation by `conversation_id`.
list_conversationsList conversations, optionally for one `agent_id` or matching text in their summaries with `summary_search`.
list_directoriesList directories. Optional filters: path, depth or ref. API summary: List Directory.
list_embeddingsList embeddings. API summary: List Embedding Models.
list_embeddings_models_list_embedding_modelsList embeddings.
list_folder_agentsList agents for a folder. Optional filters: before, order or order by. Results are paginated. API summary: List Agents For Folder.
list_folder_filesList the files in a folder by `folder_id`; set `include_content` to true to include file text.
list_folder_passagesList passages for a folder. Optional filters: before, order or order by. Results are paginated. API summary: List Folder Passages.
list_foldersList data folders (sources) of documents, optionally filtered by `name`.
list_historiesList histories. Optional filters: file path. Results are paginated. API summary: Get File History.
list_mcp_server_toolsList tools for a mcp server. API summary: List Tools For Mcp Server.
list_mcp_serversList mcp servers.
list_memory_blocksList the core memory blocks (such as persona and human) of an agent by `agent_id`.
list_metadataList metadata. Optional filters: include detailed per source metadata. API summary: Retrieve Metadata.
list_modelsList the language models available for agents, optionally filtered by provider.
list_projectsList projects. Optional filters: before, order, order by or active. Results are paginated. API summary: List Jobs.
list_run_messagesList messages for a run. Optional filters: before, order or order by. Results are paginated. API summary: List Messages For Run.
list_run_metricsList metrics for a run. API summary: Retrieve Metrics For Run.
list_run_stepsList steps for a run. Optional filters: before, order or order by. Results are paginated. API summary: List Steps For Run.
list_run_tracesList traces for a run. Results are paginated. API summary: Retrieve Trace For Run.
list_run_usagesList usages for a run. API summary: Retrieve Usage For Run.
list_runsList agent runs, filtered by `agent_id`, `conversation_id`, `statuses` or `active`. Use to check on background work.
list_server_toolsList tools for a server. API summary: List Mcp Tools By Server.
list_serversList servers. API summary: List Mcp Servers.
list_step_messagesList messages for a step. Optional filters: before, order or order by. Results are paginated. API summary: List Messages For Step.
list_step_metricsList metrics for a step. API summary: Retrieve Metrics For Step.
list_step_tracesList traces for a step. API summary: Retrieve Trace For Step.
list_stepsList steps. Optional filters: before, order, order by, start date, end date or model. Results are paginated.
list_template_snapshotsList snapshots for a template. API summary: Get template snapshot (Cloud-only).
list_template_versionsList versions for a template. Results are paginated. API summary: List template versions (Cloud-only).
list_toolsList the tools available in your Letta account, optionally filtered by `name` or `search`. Use to find a tool ID to attach to an agent.
list_variablesList variables. API summary: Retrieve Memory Variables.
retrieve_blockGet one block by block id. API summary: Retrieve Block.
retrieve_folderGet one folder by folder id. API summary: Retrieve Folder.
retrieve_messageGet one message by message id. API summary: Retrieve Message.
run_mcp_toolChanges dataCreate a new run for a tool. API summary: Run Mcp Tool.
search_all_messagesChanges dataSearch messages. Use this to find existing messages before creating a new message. API summary: Search All Messages.
search_archival_memorySearch an agent's archival memory by meaning: pass `agent_id` and a `query`, optionally `tags`, `top_k` or a date range.
search_archivesSearch archives by before, order, order by, name or agent id. Use this to find existing archives before creating a new archive. Results are paginated. API summary: List Archives.
search_blocksSearch blocks by label, templates only, name, identity id, identifier keys or project id. Use this to find existing blocks before creating a new block. Results are paginated. API summary: List Blocks.
search_conversationsChanges dataSearch messages. Use this to find existing messages before creating a new message. API summary: Search Conversations.
search_deployed_agentsChanges dataSearch agents. Use this to find existing agents before creating a new agent. API summary: Search Deployed Agents.
search_messagesChanges dataSearch messages. Use this to find existing messages before creating a new message.
search_passagesChanges dataSearch passages. Use this to find existing passages before creating a new passage.
search_tagsSearch tags by before, order, order by or name. Use this to find existing tags before creating a new tag. Results are paginated. API summary: List Tags.
search_templatesSearch templates by exact, version, template id, name, search or project slug. Use this to find existing templates before creating a new template. Results are paginated. API summary: List templates (Cloud-only).
search_tools_searchChanges dataSearch tools. Use this to find existing tools before creating a new tool.
send_agent_messageVisible to othersSend a message to an agent and get its reply: pass `agent_id` and the text in `input`. Set `streaming` to false. The agent may call its tools and update its memory while answering.
send_conversation_messageVisible to othersSend a message in a conversation and get the agent's reply: pass `conversation_id` and the text in `input`. Set `streaming` to false.
submit_documentVisible to othersClose a document (file id). Has effects visible outside this system. API summary: Close File For Agent.
submit_document_allDeletesClose a document (agent id). Destructive action; may require approval. API summary: Close All Files For Agent.
submit_mcp_serverVisible to othersRefresh a mcp server (mcp server id). Has effects visible outside this system. API summary: Refresh Mcp Server Tools.
submit_message_raw_payloadVisible to othersPreview a message (agent id). Has effects visible outside this system. API summary: Preview Model Request.
submit_message_raw_payload_previewVisible to othersPreview a message (conversation id). Has effects visible outside this system. API summary: Preview Conversation Model Request.
update_agentChanges dataUpdate an agent by `agent_id`: change its `name`, `description`, `system` prompt, `model`, `tags` or `tool_ids`. Only the fields you pass change.
update_agent_messagesVisible to othersUpdate an existing message identified by agent id. Only the fields you pass are changed. Has effects visible outside this system. API summary: Reset Messages.
update_approvalChanges dataUpdate an existing approval identified by tool name. Only the fields you pass are changed. API summary: Update Approval For Tool.
update_archiveChanges dataUpdate an existing archive identified by archive id. Only the fields you pass are changed. API summary: Update Archive.
update_document_opensVisible to othersUpdate an existing open identified by file id. Only the fields you pass are changed. Has effects visible outside this system. API summary: Open File For Agent.
update_folderChanges dataUpdate an existing folder identified by folder id. Only the fields you pass are changed. API summary: Update Folder.
update_mcp_serverChanges dataUpdate an existing mcp server identified by mcp server id. Only the fields you pass are changed. API summary: Update Mcp Server.
update_memory_blockChanges dataChange an agent's core memory block by `agent_id` and `block_label`: pass the new `value`, and optionally `description` or `limit`. The new text replaces the old.
update_messageChanges dataUpdate an existing message identified by message id. Only the fields you pass are changed. API summary: Update Conversation.
update_serverChanges dataUpdate an existing server identified by mcp tool name. API summary: Add Mcp Tool.
update_serversVisible to othersUpdate an existing server. Has effects visible outside this system. API summary: Add Mcp Server To Config.
update_step_feedbackVisible to othersUpdate an existing feedback identified by step id. Only the fields you pass are changed. Has effects visible outside this system. API summary: Modify Feedback For Step.
update_templateChanges dataUpdate an existing template identified by template name. API summary: Save template version (Cloud-only).
update_template_descriptionsVisible to othersUpdate an existing description identified by template name. Only the fields you pass are changed. Has effects visible outside this system. API summary: Update template description (Cloud-only).
update_template_documentsVisible to othersUpdate an existing document identified by template name. Has effects visible outside this system. API summary: Update current template from agent file (Cloud-only).
update_template_namesVisible to othersUpdate an existing name identified by template name. Only the fields you pass are changed. Has effects visible outside this system. API summary: Rename template (Cloud-only).
update_template_snapshotsVisible to othersUpdate an existing snapshot identified by template version. Has effects visible outside this system. API summary: Set current template from snapshot (Cloud-only).
update_toolChanges dataUpdate an existing tool identified by tool id. Only the fields you pass are changed. API summary: Update Tool.
update_toolsVisible to othersUpdate an existing tool. Has effects visible outside this system. API summary: Upsert Tool.

Set up in three steps

1
Pick the app
Create a free HeyMyApps account and choose Letta from the app list.
2
Paste your key
Paste a Letta API key. Log in at platform.letta.com, open API keys, create a key and copy it.
3
Add the link to your AI
You get a personal MCP link. Add it to Claude, ChatGPT or Cursor:
1. Click your name, then Settings › Connectors › Add custom connector.
2. Paste your link as the Remote MCP server URL.
3. Switch it on from the + menu in a chat.

Questions

What can the AI do in Letta?

The AI can list and read agents, memory blocks, archival memory, conversations, messages, runs, tools, folders and models. It can update agents and memory blocks, add and delete archival memory, attach and detach tools, start conversations and send messages to agents.

Does the AI see my Letta API key?

No. Your Letta API key and settings are encrypted at rest and never shown to the AI. After you save them, they are not shown again, not even to you. The AI only sees the results of the tools it calls.

Can I control what the AI is allowed to do?

Yes. You choose which tools are switched on, so you can start read-only. Sending a message makes the agent act and possibly change its memory, and deleting archival memory is permanent. These actions can require your approval before they run. Every tool call is logged.

Does it work with ChatGPT?

Yes. In ChatGPT go to Settings › Apps & Connectors › Advanced and turn on Developer mode, then add your HeyMyApps link. Developer mode needs a paid ChatGPT plan: Plus, Pro, Business or Enterprise. The same link also works in Claude (Settings › Connectors › Add custom connector), Cursor and other MCP clients.

What does it cost?

HeyMyApps has a free plan with no credit card required. Paid plans bill per completed task. You also need your own Letta account.

What is the difference between core memory and archival memory?

Core memory blocks, such as persona and human, are short texts the agent always has in view. The AI can read a block or replace its text. Archival memory is a long-term store of passages the agent searches when needed. The AI can list, search, add and delete those passages.