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[Update! Multi-workspace, comments and more!] | Introducing the official Trello MCP server!

Melody

📣 Update — September 28, 2026

Attention, Trello MCP fans! We’ve got some exciting updates to share with you. Here’s a roundup of everything fresh and new:

🏢 Connect multiple workspaces

Now you can connect to multiple Trello workspaces simultaneously! Select the workspaces to connect from the workspace drop-down during authorization. Manage personal, team, and project workspaces together.

Already connected? Simply disconnect and reconnect to select as many workspaces as your heart desires (within token size limits, of course!).

💬 Comments

You asked, we delivered! Full commenting power is officially here. Ask Trello MCP to read, write, or edit card comments on your behalf.

👥 Member & activity info

Trello MCP can now access full member and activity info across your cards, boards, and workspaces. Give these a try:

Activity summaries: Ask who recently updated certain boards or commented on your cards in the past week.
Task assignments: Assign multiple cards to teammates in seconds.

Note: Assigning members directly to checklist items isn’t ready just yet. Stay tuned!

🏷️ Custom fields

For Standard, Premium, and Enterprise users: Trello MCP can now fetch custom field data across your boards and create new ones with ease.

📎 Attachments

Trello MCP can now read all card attachments. Want to add a web article as an attachment on your card? Just toss your agent the URL of the attachment!

Note: Uploading local files isn't supported yet, but link attachments are ready to roll.

🚀 What’s next?

We’re continually cooking up more MCP superpowers. Have fun exploring these new capabilities, and keep sharing your ideas and feedback with us!

Announcement

Do you like using AI? Love using Trello? If so, then this update is for you!

Today we’re launching the official Trello MCP server. The Trello MCP server acts as a secure gateway between your Trello boards and the AI assistants you already use — like Claude, ChatGPT, and more. Once connected, you can manage your Trello tasks directly from AI using natural language. No tab-switching, no copy-pasting between the two.

Here are a few things you can try once you’ve got it set up in your favorite AI tool:

• "Create a Trello board for the Italy travel plan we just discussed."
• "Show me any Trello cards due this week and book focus time on my calendar to get them done."
• "Review the tasks I have on my wedding planning board and add anything missing."
• "Move everything in my Trello Inbox onto boards."

All communication between your AI tools and Trello is encrypted and authenticated using security best practices. Your data stays yours — the MCP server is simply the secure bridge that gives your AI assistant the context it needs to help you stay organized.

Head to trello.com/mcp to learn more and connect your AI assistant to Trello today. We'd love to hear how you're using it, so drop your favorite prompts in the comments below!

Comments

JR_30ra9l

Looks interesting. What guarantees are there that my AI agent (Claude) won't delete critical cards or comments that are required for compliance and product history etc? Can hard restrictions be put on that, as we all know that Claude can break outside guard rails?

Melody

Good question, JR! Trello MCP does not support destructive delete operations. Your AI assistant cannot permanently delete Trello content because they don't have the tools to do so.

Benjamin Noss

Could integrate Trello with ChatGPT via 'Plugins' and with Claude via 'Connectors' - both worked perfectly.
Then I tried to connect Trello to Langdock (https://langdock.com/) via the new MCP. Registration/connection itself ran without errors, but after that, Langdock can't get access to the board.

The connected Trello MCP integration cannot retrieve a specific board, although the board is accessible through another Trello integration and the user’s permissions appear to be valid.

Error

Using trelloReadBoard with action get returns:

<span>Copy</span>Field "workspaceId" is not allowed for action "get"

Without workspaceId, the wrapper instead returns:

<span>Copy</span>Expected a Trello workspace ARI

Expected behavior

The board should be retrievable using its valid Trello URL or short board key, allowing lists and cards to be read and edited.

Suspected cause

The MCP wrapper appears to require and forward workspaceId, while the underlying endpoint rejects this field for the get action.

Request would be (if there wasn't only community support):

"Please check the parameter schema and request mapping for trelloReadBoard, especially the handling of workspaceId during get requests. Also verify the workspace mapping and synchronization of the connected Trello integration."

^^Can anyone here say anything about that issue?

Melody

Hi @Benjamin Noss, thanks for the feedback!

Could you try to ask your AI agent to call action="get" with only boardId, no workspaceId? Get a board is not require to pass workspaceId.

Let us know if this fixes the issue! Thanks!

Quinn Zimmerman

I need a way for Claude to connect to a board that I am a guest on since our company uses a centralized board to manage tasks. I haven't found anywhere on how to enable this, and every time I try reconfiguring the setup with my Claude connector, it only shows my workspace, which has nothing on it.

If there isn't an active solution for this, would my best bet be to use a Power-Up that copies the cards and boards from our shared board and put them in my personal workspace? Then if I archive a card have another power-up tool that reads that input and pushes an archive change to the same card that is in the shared board?

Thanks.

Melody

Hi @Quinn Zimmerman, supporting board guests in Trello MCP is not currently on our roadmap.

As a workaround, we'd recommend joining the board as a full board member if that's an option — this also avoids potential data security concerns that can arise when company data is accessed through a personal workspace. Most organizations have policies around this, so it's worth checking with your admin team as well.

Benjamin Noss

@Melody

Hi,

I tried calling action="get" with only the boardId, as suggested.

However, the MCP tool interface still requires a workspaceId value during validation. Without it, the request is rejected before it reaches Trello:

Expected a Trello workspace ARI (e.g. ari:cloud:trello::workspace/<workspaceId>). at workspaceId

So I cannot currently perform a get request with only boardId through this AI agent. It appears that workspaceId is mandatory in the MCP tool schema, even though it should be optional for the get action.

Could you please adjust the schema or validation so that workspaceId is optional when action="get"?

Thanks!

Melody

Hi @Benjamin Noss,

We just released a fix for this issue. Could you refresh the Trello MCP toolsets (or simply disconnect and reconnect) and try again? Hopefully this should solve the problem.

Let us know how it turned out! Thanks!

Michael Kyed

Great to see an official MCP server!

One concrete request: reading card comments. Often decisions etc. hides there...

Melody

Hi @Michael Kyed, thanks for the feedback! We are actively working on it right now! It's a popular demand. We'll let you know once card comments capability is released in our MCP. Stay tuned!

Benjamin Noss

@Melody tried everything to post you some useful information about the problem that your MCP still doesn't work (at least in Langdock) - but this annoying editor blocks it all the time. Don't know how long I'm sitting at this already. It just spills out this error message but DOESN'T show, WHERE to find this "invalid HTML".
As far as I can say I have stripped all obvious HTML... A really bad experience... sad.

Screenshot 2026-09-07 191146.png

Benjamin Noss

@Melody 2nd try with just plain text which is horrible to read - so as horrible as this editor here...

It still doesn't work with Langdock (https://langdock.com/):

Error Description: Valid board cannot be read and prevents the creation of a card

Ticket type: Bug
Affected function: Trello integration
Date of occurrence: 07/09/2026
Priority: High
Status: Open

Summary

I wanted to create a new card named TEXT in the list Trello into 'collection board' via the Trello MCP integration.

The card could not be created because the integration was unable to read the relevant board directly or retrieve the lists it contains, despite a valid Trello link. Several requests were rejected with contradictory validation errors. As a result, the required board identifier and the identifier of the target list could not be determined.

Expected behavior

The Trello integration should enable the following steps:

Accept a valid Trello board link.
Resolve the associated board unambiguously.
Retrieve the board's open lists.
Identify the list named Trello.
Create a new card named TEXT in this list.
After successful creation, return the card data or at least a clear success message.

Actual behavior

The integration was unable to resolve the board reliably. Depending on the request used, one of the following errors occurred:

The search request was rejected with Trello AGG GraphQL error: Unable to validate input.
The direct board request required a workspace field, although according to the error message this field was not permitted for the get action.
Without a workspace field, validation reported that a valid workspace identifier was required.
The list retrieval did not accept the passed board link and instead requested a board identifier in ARI format.
Using a board abbreviation also led to validation due to missing or invalid additional parameters.
An attempt to read the board via the card query was also rejected due to invalid placeholder values for card, comment and list fields.
The TEXT card was not created.

Initial situation and requested action

I requested the following action:

Create a new card named TEXT in the list Trello in the 'collection board'.

Because the technical identifier of the target list is required to create a card, the integration should first read the board and then the list.

The first search for the board was unsuccessful. I then provided the complete Trello link to the board.

Steps to reproduce

Variant A: Search for the board

Open the Trello integration.
Start a board search using a unique part of the board name or the whole board name.
Restrict the search to the available workspace or run it without a workspace filter.
Evaluate the result.

Result:

Trello AGG GraphQL error: Unable to validate input

The error occurred both when searching with a general search term and when searching within the known workspace.

Variant B: Direct board request via the board URL

Pass the valid board link to the function for reading a single board.
First run the request without a workspace identifier.

Result:

MCP error -32602: Input validation error: Invalid arguments for tool trelloReadBoard: Expected a Trello workspace ARI (e.g. ari:cloud:trello::workspace/<workspaceId>). at workspaceId

Then repeat the request with the previously determined workspace identifier.

Result:

Field "workspaceId" is not allowed for action "get"
The validation requirements therefore contradict each other:
Without workspaceId, the field is treated as required.
With workspaceId, the field is treated as invalid for the same action.

Variant C: Retrieve the lists via the board URL

Use the function for reading a board's lists.
Pass the complete Trello board link as the board identifier.

Result:

MCP error -32602: Input validation error: Invalid arguments for tool trelloReadList: Expected a Trello board ARI (e.g. ari:cloud:trello::board/workspace/<workspaceId>/<boardId>). at boardId

Expected a Trello list ARI (e.g. ari:cloud:trello::list/workspace/<workspaceId>/<listId>). at listId

According to its description, the function accepts a board ARI. However, a board link is not accepted. At the same time, the list identifier is not yet known because the lists could not be read beforehand.

Variant Retrieve data via the card function

Run the card request for the relevant board.
Have the open cards grouped by list.

Result:

The request was rejected because of invalid values for several required fields. Among other things, the error message referred to the following expected formats:

Expected a Trello card ARI or a card URL at cardIdOrUrl
Expected a Trello action ARI at commentId
Expected a Trello list ARI at listId

No individual card or comment ID was known for the requested action. Using placeholder values triggered additional input validation and did not permit the board or list data to be retrieved.

Technical context

The workspace could be determined in principle. The integration returned the following data:

Workspace name: xyz
Workspace identifier: ari:cloud:trello::workspace/xyz
Workspace status: accessible
Additional workspaces: none

This means that basic access to the Trello workspace exists. The error occurs when subsequently resolving or reading the specific board. In my Atlassian Profile under 'Connected Apps' as well as under Langdock Integrations everything looks fine - no errors and status connected.

Technical observations

1. Contradictory parameter rules

The function for directly reading a board behaves inconsistently:

Validation requires a workspace identifier.
The GraphQL request rejects the same workspace identifier as invalid for the get action.
This indicates a discrepancy between the published tool description, the input validation, and the GraphQL schema actually being used.

2. Different identifier formats without a working transition

The functions involved expect different identifier formats:

Board URL or board shortlink for the direct request
Board ARI for the list request
List ARI for creating a card
Card ARI for card actions

A valid transition from the board URL to the board ARI and then to the list ARI was not possible because the initial board request already failed.

3. Missing safe handling of unknown IDs

In a normal user action, the board and list IDs are initially unknown. The integration must determine these IDs from a board link or via a board search.

When placeholder values are used for unknown IDs, they are validated as invalid ARIs. This means there is no robust fallback if a preceding search function fails.

4. Search function unusable

The search for boards and cards was rejected with the same GraphQL validation error:

Trello AGG GraphQL error: Unable to validate input
The search could therefore be used neither as the primary method for determining the board nor as a fallback method.

Impact

The issue prevents the complete creation of a card via the Trello integration.

At least the following steps are affected:

Resolving a board via a URL
Listing a board's lists
Identifying a list by its name
Creating a card in a list whose technical identifier is not known in advance
Using the board search as a fallback
Using the card request as a fallback

This restriction means that a simple card creation must be performed manually in Trello or that the technical ID of the target list must be obtained by another means beforehand.

Expected error handling

If a board link is valid, the integration should either:

read the board directly and return its lists, or
return a clear, understandable error message that states the specific reason.
The integration should avoid contradictory required-field errors. In particular, a field must not be treated as both required and invalid for the same action.
If the board search is temporarily unavailable, the direct request via a board URL should continue to work.
If the list ID is not yet known, the integration should be able to resolve the list by name. Entering placeholder IDs must not be required.

Suspected error class

The symptoms observed indicate an error in at least one of the following areas:

Input validation of the Trello tools
Mapping of parameters to the individual actions
GraphQL schema or GraphQL variables of the Trello aggregation layer
Processing of board URLs and board shortlinks
Discrepancy between the tool description and the actual implementation
Missing resolution chain from board URL to board ARI to list ARI
Insufficient handling of optional parameters for individual actions

These points are to be understood as technical areas for investigation. A definitive cause cannot be derived from the user behavior alone.

Requested correction

The Trello integration should enable card creation using the following flow:

Accept the board URL.
Validate the board URL.
Resolve the board URL to a valid internal board identifier.
Retrieve the board and its open lists.
Identify the list Trello by name.
Create the card TEXT in the identified list.
Confirm success with the card name, target list, and board link.

If the board is inaccessible, the error message should clearly distinguish between the following cases:

Invalid board link
Board not found
Missing permission
Board closed or archived
List not found
Temporary service error
Internal validation error

Acceptance criteria

A valid Trello board link can be processed through the direct board request.
The direct board request works without contradictory requirements concerning workspaceId.
A board's lists can be loaded starting from a board URL or a valid board ARI.
The board search returns results for valid search parameters or a technically meaningful error message.
The card request does not require unknown card, comment, or list IDs as placeholders.
The list Trello can be found by name.
A card named TEXT can be created in this list.
After successful creation, the newly created card is returned unambiguously.
In the event of an error, no contradictory or misleading required-field messages are returned.
The tool description and the actual input validation match for all affected actions.

Error messages relevant to the technical investigation

Trello AGG GraphQL error: Unable to validate input

MCP error -32602: Input validation error: Invalid arguments for tool trelloReadBoard: Expected a Trello workspace ARI (e.g. ari:cloud:trello::workspace/<workspaceId>). at workspaceId

Field "workspaceId" is not allowed for action "get"

MCP error -32602: Input validation error: Invalid arguments for tool trelloReadList: Expected a Trello board ARI (e.g. ari:cloud:trello::board/workspace/<workspaceId>/<boardId>). at boardId
Expected a Trello list ARI (e.g. ari:cloud:trello::list/workspace/<workspaceId>/<listId>). at listId

MCP error -32602: Input validation error: Invalid arguments for tool trelloReadCard: Expected a Trello card ARI (e.g. ari:cloud:trello::card/workspace/<workspaceId>/<cardId>) or a card URL (https://trello.com/c/<shortLink>/...). at cardIdOrUrl
Expected a Trello action ARI (e.g. ari:cloud:trello::action/<actionId>). at commentId
Expected a Trello list ARI (e.g. ari:cloud:trello::list/workspace/<workspaceId>/<listId>). at listId

Outcome of the process

The requested card was not created.

Based on the observed behavior, the cause lies in the communication between the Trello integration and the underlying Trello query layer. The provided board link was available as a starting point. Nevertheless, it was not possible to successfully resolve the board and the target list.

Edit: Quick format edit to increase readability.

Jinhuan Lei

Hi @Benjamin Noss , Thanks for sharing the troubleshooting note here.

I did some research from our end,

Regarding the error encountered with the `trelloReadBoard` tool for the `get` action, the error `Field "workspaceId" is not allowed for action "get"` indicates that the langdock MCP client is sending a value when it should not. It is a known issue that some MCP clients incorrectly send empty strings to optional fields. By confirming this, you can ask what the raw input params langdock use for tool call. You may want to use a prompt to guide langdock to avoid passing any value, including empty strings, for optional fields.

The Search function is currently unusable due to the error "Unable to validate input." This occurs because the langdock client passes an incorrect cursor value, which is the value returned in the previous search response. We will push a fix to return a more agent-friendly error message from our end. In the meantime, you may need to guide langdock to properly extract the cursor value from the previous search response to temporarily unblock your search experience.

Benjamin Noss

@Jinhuan LeiI already have feedback to this:

Regarding the thesis "empty string in optional fields": Our MCP client removes empty optional string fields before the actual tool call is made. An optional field like “workspaceId” would not be transferred to Trello as an empty string in the current version. The cursor also doesn't run through Trello-specific logic, but through the same generic filter and validation path as all other tool parameters.

However, there is one structural point that we take seriously: we store each tool field with a simple "required" flag. Action-dependent rules in which a field is required for one action but not permitted for another (e.g. “list” vs. “get”) cannot always be mapped cleanly.

This can lead to conflicts such as the “workspaceId” message on “get”. We look at the topic of how optional tool inputs are handled across integrations. However, I cannot give you a reliable implementation or time frame for this.

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