The public Klientele API.

Example: a law firm's client portal logs a matter task. The fields are the request fields; your industry template decides what they are called in the app, and the reference number uses your workspace's prefix.

curl -X POST https://api.klientele.io/api/public/v2/requests \
  -H "X-API-Key: kl_live_••••••••" \
  -H "Content-Type: application/json" \
  -d '{
    "clientId": "b3f1c9e0-2a4d-4e3a-9c1e-6d2a7f8e0b11",
    "title": "Review the revised lease before Friday",
    "description": "Landlord sent a new draft. Clause 7 now caps the break option at 12 months.",
    "urgency": "high",
    "reporterName": "Priya Shah",
    "reporterEmail": "[email protected]",
    "tags": ["lease", "deadline"]
  }'

{
  "status": "success",
  "data": {
    "id": "6f0d2c1a-8e4b-4b7e-9a51-3c2d7e9f1a04",
    "requestNumber": "TASK-2026-0042",
    "status": "new",
    "source": "api",
    "createdAt": "2026-10-04T09:12:44.512Z"
  }
}

Files can travel with the create. Add an attachments array to a request, planned item or engagement: each entry is either { "fileName", "base64" } or { "url" } for a public https file we download for you. Up to 10 files; your workspace's allowed file types and size limit apply. One refused file refuses the whole call and nothing is created. Inline content counts towards the 10 MB request limit, so send larger files by URL. Attaching needs the key to hold attachment.create.

curl -X POST https://api.klientele.io/api/public/v2/requests \
  -H "X-API-Key: kl_live_••••••••" \
  -H "Content-Type: application/json" \
  -d '{
    "clientId": "b3f1c9e0-2a4d-4e3a-9c1e-6d2a7f8e0b11",
    "title": "Countersign the lease",
    "urgency": "high",
    "attachments": [
      { "url": "https://files.example.com/lease-v3.pdf" },
      { "fileName": "notes.txt", "base64": "Q2xhdXNlIDcgY2hhbmdlZC4=" }
    ]
  }'

<script
  src="https://api.klientele.io/widget/v1/klientele.js"
  data-key="kl_pub_••••••••"
  data-client-id="b3f1c9e0-2a4d-4e3a-9c1e-6d2a7f8e0b11"
  defer
></script>

Requests that come in through the widget, the API or the email inbox count towards your plan's monthly allowance of external requests.

Most MCP clients, Claude included, only need the URL: add it, sign in to Klientele and choose what the app may do: read only, read and write, or full access. The agent acts as you and can never do more than your role allows. A workspace admin can switch API access off for everyone. Using Claude? Follow Connect Klientele to Claude.

The server offers more than 200 tools across requests, planned items, engagements, cycles, clients, comments, attachments, time and timers, deliverables and milestones, expenses and their receipts, retainers, invoices, payments and credit notes, plus reports and notifications. Five of them open interactive views in Claude. Tool titles use your workspace's own words, so a law firm sees matter tasks where a software team sees tickets. It does not administer the workspace: roles, API keys, webhooks, settings, import, export and team invitations stay in the app.

Sign-in uses OAuth 2.1 with dynamic client registration and PKCE. Claude, Cursor and OpenAI Codex all support it. A client that can only use a pre-registered client ID cannot sign in yet; give it a server key instead.

claude mcp add --transport http klientele https://mcp.klientele.io/mcp

{
  "mcpServers": {
    "klientele": { "url": "https://mcp.klientele.io/mcp" }
  }
}

[mcp_servers.klientele]
url = "https://mcp.klientele.io/mcp"

Scripts, CI jobs and clients that cannot sign in send a server key as a bearer token instead. The key acts as the member who created it, with the permissions ticked when it was made. Keep it in an environment variable:

claude mcp add --transport http klientele https://mcp.klientele.io/mcp \
  --header "Authorization: Bearer ${KLIENTELE_API_KEY}"

[mcp_servers.klientele]
url = "https://mcp.klientele.io/mcp"
bearer_token_env_var = "KLIENTELE_API_KEY"

Send an Idempotency-Key header on any POST, PATCH or DELETE: 8 to 200 characters of letters, digits and . _ : -, new for each change you mean to make. If the connection drops, send the same request with the same key. For 24 hours, a retry that matches the original gets the original response back with Idempotent-Replayed: true, and nothing happens twice. Keys belong to the member the key acts as.

curl -X POST https://api.klientele.io/api/public/v2/requests \
  -H "X-API-Key: kl_live_••••••••" \
  -H "Idempotency-Key: 01JB9Z6Q8W7X3K5M2N4P6R8T0V" \
  -H "Content-Type: application/json" \
  -d '{ "clientId": "b3f1c9e0-2a4d-4e3a-9c1e-6d2a7f8e0b11", "title": "Review the lease", "urgency": "high" }'

A match means the same method, path, query and body; files count by their content. Any answer other than a success frees the key, so you can fix the request and send it again with the same key. The ways a key is refused:

• 409 IDEMPOTENCY_CONFLICT: the key was already used for a different request. Use a new key.
• 409 IDEMPOTENCY_IN_PROGRESS: the first attempt is still running. Wait for the Retry-After seconds and send it again.
• 409 IDEMPOTENCY_RESPONSE_UNAVAILABLE: the first attempt worked, but its response was over 1 MB, too large to keep. Read the result instead.
• 400 IDEMPOTENCY_KEY_INVALID: the key is not 8 to 200 of the allowed characters.

The MCP server sends a key with every tool that writes, so an agent that repeats a call after a timeout does not repeat the change.

Every request and planned item carries a version. Send the version you read with your update. If someone changed the item since, the update is refused with409 EDIT_CONFLICT and nothing is written. Without aversion, the update is not checked against what you read.

curl -X PATCH https://api.klientele.io/api/public/v2/requests/7d0c…e21 \
  -H "X-API-Key: kl_live_••••••••" \
  -H "Content-Type: application/json" \
  -d '{ "urgency": "critical", "version": 4 }'

The conflict tells you what to do next:

• fields: every field changed since your version, withtheirs (stored now), mine (what you sent) andoverlap (you both changed it, to different values).
• current: the item exactly as a GET returns it, andcurrentVersion. Apply your change on top and send it again with that version.
• changedBy and changedAt: who made the change and when.

Sending the same values twice is safe: an update whose values already match what is stored succeeds and changes nothing. Bulk updates take versions (one per id) and refuse the whole batch if any of them is stale. The MCP server sends the version an agent last read for you.