hdls Chat

hdls Chat is a headless, MCP-native team & cross-org messaging backend. It manages channels, messages, members, and cross-org connections, operated entirely through named tools your AI assistant calls. It stands in for tools like Slack, Microsoft Teams — same job, no UI to run.

💬 Just ask

"Start a #launch channel, post the kickoff note, and add the team."

You don't call these tools yourself — just tell your assistant in plain English. Everything below is the reference for when you (or your assistant) want the exact details.

How Chat is organized

The headline entity is the message — start there, then attach the rest to it. Records connect by reference: a channel links to a connection; a membership links to a channel. The message table is an append-only timeline — every change and note lands there and is never edited or deleted.

Entity	Purpose	Relates to
`message`	Append-only messages. origin=federated marks a copy received from a peer org.	`channel`
`channel`	A channel/conversation. kind=external federates to a peer org via the events engine.	`connection`
`connection`	A trusted link to another org; cross-org messages federate over signed webhooks.	—
`membership`	Who (user/agent) is in a channel and their role.	`channel`

Common workflows

Each line is one real sequence of tool calls — your assistant chains them for you.

Set up a message end to end: create_channel → post_message → add_member

Tools

Call these at https://hdls.ai/api/mcp/chat. Required fields you must supply; optional fields refine the call. You never pass tenant_id — it is stamped server-side.

Create

Tool	What it does	Required	Optional
`create_channel`	Create a new channel.	`name`	`kind`, `topic`, `connection_id`, `data`

Update & advance

Tool	What it does	Required	Optional
`add_member`	Add a member.	`id`	—
`connect_org`	Connect an org.	`id`	—

Find & read

Tool	What it does	Required	Optional
`search_messages`	Search messages by free-text and/or column filters (tenant-scoped, paginated).	—	`search`, `filters`, `limit`, `orderBy`
`list_channels`	Search channels by free-text and/or column filters (tenant-scoped, paginated).	—	`search`, `filters`, `limit`, `orderBy`

Timeline

Tool	What it does	Required	Optional
`post_message`	Post a message.	`channel_id`, `body`	`parent_id`, `author_type`, `author_id`, `origin`, `data`

Field lists come from the product's live schema and are embedded in each tool's own description — read the tool description for the exact, current fields.

Field reference

Every field you can set on each record. Custom fields you add live alongside these in data.

`channel`

Field	Type	Required	Notes
`name`	text	Yes	Display name.
`kind`	text
`topic`	text
`connection_id`	id		Links to a `connection`.
`data`	json		Free-form JSON — custom fields live here.

`connection`

Field	Type	Required	Notes
`peer_tenant_id`	id	Yes	Reference to a related record.
`peer_label`	text
`status`	text		Lifecycle state.
`data`	json		Free-form JSON — custom fields live here.

`membership`

Field	Type	Required	Notes
`channel_id`	id	Yes	Links to a `channel`.
`member_type`	text
`member_id`	text	Yes	Reference to a related record.
`role`	text
`joined_at`	timestamp

Tailor it with custom fields

Add fields without a schema change. add_custom_field defines one, list_custom_fields shows what's defined, and promote_custom_field (admin) shares a personal field with the whole workspace. The value lives in each row's data (JSON) and is set and read through the normal record tools. See Products, tools & custom fields for the full model.

Roles & safety

Tenant isolation is automatic. Your credential is pinned to one workspace; you never pass tenant_id, and you can only ever see your own data (enforced by Postgres row-level security).
Role-gated. Permissions run reader < member < admin < owner. Installing a product and promoting a custom field workspace-wide need admin/owner.
History is append-only. The message timeline is never edited or deleted — it's your audit trail.

Connect

On the concierge (https://hdls.ai/api/mcp), run install_product({ slug: "chat" }) (admin/owner) to enable it for your workspace, then add https://hdls.ai/api/mcp/chat as a connector in your assistant — see Connect your assistant.

A worked example

The literal call your assistant makes when you ask it to create the headline record:

Tool: create_channel
Arguments: {
  "name": "Acme Corp"
}

See All products · Connect your assistant · Automation