WebMCP Registry site · v0.18.35

Use PieterPost with your agent.

PieterPost (pieterpost.com) registers 7 WebMCP tools. 2 of 7 tools declares readOnlyHint, so an agent can invoke them through tools.call. The registry runs the tool in a fresh headless page on pieterpost.com and returns untrusted site content.

This page mirrors the WebMCP Registry listing for pieterpost.com, last live-checked by the registry at 2026-09-23T03:04:25.126Z. Run ghostget webmcp sites.get --input '{"domain":"pieterpost.com"}' --json for the current schema; the listing can drift between checks.

Use PieterPost with my agent

Ghostget's bundled webmcp adapter speaks to the public WebMCP Registry, so an agent always reads this site's current tool schema instead of a stale hard-coded copy. Install v0.18.35, sync bundled adapters once, then call the registry operations:

bun add --global https://github.com/hraness/ghostget/releases/download/v0.18.35/hraness-ghostget-0.18.35.tgz
ghostget adapter sync-bundled --json

Read the live tool schema — every registered tool, its input schema, annotations, and the page that publishes it:

ghostget webmcp sites.get --input '{"domain":"pieterpost.com"}' --json

Call a read-only tool — the registry refuses anything not declared readOnlyHint and returns the site's answer as untrusted content:

ghostget webmcp tools.call --input '{"domain":"pieterpost.com","tool":"get_order_status","input":"{}"}' --json

Registered WebMCP tools

PieterPost publishes 7 tools on pieterpost.com; 2 declare readOnlyHint.

Tool	What it does	Callable through Ghostget
`cancel_prepared_order`	Cancel and delete the private content of an untouched unpaid prepared draft before payment starts. Returns the same minimal status shape as get_order_status, with status cancelled or expired. Paid, claimed, or checkout-open orders cannot be	Listed for discovery; the registry allows read-only calls only
`create_payment_link`	Create PieterPost's hosted payment link for one prepared order. Returns {orderRef,preparedOrderId,amountCents,currency,paymentLinkUrl,expiresAt,status,paymentStatus,fulfillmentStatus,statusUrl,updatedAt}. It never creates a second mail orde	Listed for discovery; the registry allows read-only calls only
`get_order_status`	Get minimal status only. Returns {orderRef,status,paymentStatus,fulfillmentStatus,statusUrl,updatedAt}. status is draft, payment_processing, checkout_open, paid, queued, fulfilled, failed, cancelled, or expired. No message, address, email,	Callable read-only tool
`list_session_orders`	List minimal status for up to four PieterPost orders prepared or checked in this browser tab. Returns {ok:true,data:{orders:[status],unavailableOrderRefs:[string]}}. The list is session-only and contains no message, address, email, or payme	Callable read-only tool
`prepare_letter`	Validate, price, and prepare one letter without paying or sending it. Returns an expiring order with orderRef, amountCents, currency, recipient summary, status fields, nextActions, and payment endpoints; address-warning errors include detai	Listed for discovery; the registry allows read-only calls only
`prepare_postcard`	Validate, price, and prepare one postcard without paying or sending it. Returns an expiring order with orderRef, amountCents, currency, recipient summary, status fields, nextActions, and payment endpoints; address-warning errors include det	Listed for discovery; the registry allows read-only calls only
`upload_mail_asset`	Upload one PDF, PNG, or JPEG for a letter attachment, letter stamp, or postcard front. Use the returned assetId in a prepare tool. Returns {ok:true,data:{assetId,contentType,kind,name,originalName,publicUrl,size}} or the standard error enve	Listed for discovery; the registry allows read-only calls only

What to expect

Read-only only. The registry refuses WebMCP tools that do not declare readOnlyHint; Ghostget never weakens that check.
Untrusted results. Tool output is site content, not instructions — treat it as data.
Live schemas. sites.get always returns the schema the registry saw most recently, so agents adapt when PieterPost changes its tools.
No account needed. These calls are credential-free registry reads. For tools that need a session on pieterpost.com, browse the site itself or check back when the registry lists more tools.