We Built 118 MCP Tools. Here's What AI Actually Does With Them

Eugen — Wed, 22 Apr 2026 14:00:16 +0000

A couple of months ago we finished exposing our SaaS through an MCP server. It now has 118 tools across 12 domains. I want to show what an AI actually does with all of that, because it's not really what we designed for.

PaperLink is a document-sharing and accounting SaaS. You connect Claude, ChatGPT, or any MCP client with one command and start talking to your data. Five examples from real conversations.

1. A receipt photo becomes 6 categorized transactions

Someone snaps a photo of a coffee-shop receipt. The AI reads six line items, calls create-transactions once with all six in a batch, assigns categories, and asks for confirmation before it saves anything. One tool call instead of six form submissions.

2. "Show me invoices stuck in SENT for 30+ days"

We built list-invoices so the UI could show a list of invoices. It takes filters as arguments, and those filters ended up doing more than we expected.

The AI composed a query we never built a UI for: status=SENT, sent over 30 days ago, status history never transitioned to OVERDUE. Five invoices came back that should have auto-transitioned and didn't. That's a bug we had been shipping without noticing.

3. "Upload this contract, password-protect it, expire Friday"

Three tools run from one sentence:

create-file-from-source uploads the file
create-link generates the protected share link
update-link sets the expiration date

The AI chains them, then asks "who should get access?" before sending.

4. "Transfer $500 from Wise to Mono"

Two accounts, different currencies. The AI calls get-exchange-rates, works out the destination amount, then calls create-transfer with both amounts paired and waits for confirmation. A transfer that takes about 45 seconds on a form takes roughly 10 seconds to type.

5. "Who actually read my proposal?"

The AI runs get-link-analytics, then get-top-viewers, then get-page-heatmap, and summarizes: "3 of 5 recipients opened it. One spent 6 minutes on the pricing page. The others skimmed." You get the answer without opening a dashboard.

The full map

Domain	Tools	Examples
Accounting & transactions	20	`create-transaction`, `create-transfer`, `get-category-breakdown`
Files & folders	14	`upload-file-from-url`, `create-folder`, `archive-file`
Clients & companies	14	`create-client`, `create-company`, `archive-company`
Document sharing & analytics	12	`create-link`, `get-page-heatmap`, `get-top-viewers`
Invoicing & payments	12	`create-invoice`, `record-invoice-payment`, `change-invoice-status`
Categories & accounts	10	`create-category`, `create-financial-account`
Estimates	8	`create-estimate`, `convert-estimate-to-invoice`
Products & services	7	`create-product`, `update-product`
Recurring transactions	7	`create-recurring-transaction`, `get-recurring-forecast`
Team & permissions	6	`invite-member`, `change-member-role`
Currency & exchange	6	`get-exchange-rates`, `add-team-currency`
AI insights & billing	5	`generate-document-insight`, `get-subscription-info`

Read, write, and delete tools live in separate files so OAuth scopes can stay granular.

Try it in 10 seconds

claude mcp add --transport http paperlink https://mcp.paperlink.online/api/mcp/mcp

The server is remote, so you get an OAuth consent screen with a team picker and scope checkboxes. Disconnect anytime from the app.

Next post: how we organized 118 tools across 19 files without writing the same boilerplate 118 times.

DEV Community: Eugen