Inbox eSIM MCP server

• Registry namecom.inboxesim/esimverified in the MCP registry

The registry name sits under inboxesim.com. The registry only lets a publisher use that namespace after proving control of the domain through DNS or HTTP.

• Stateanswerschecked 2026-10-29
• Tools5
• Server calls itselfinbox-esim
• Server version1.0.0
• Protocol version2025-06-18

On 2026-10-29 the server answered initialize and tools/list without a sign-in. First answer in 304 ms.

• Its tools do buy a data plan for a destination country, but not install an eSIM by scanning an emailed QR code; top up an existing eSIM on a repeat trip.
• Checked on 6 of the 7 days it takes to judge reliability.

Said by rules from the measurements above. The likely first call is a model's pick from the tool list; read its description before relying on it.

• INITE MCP scoreafter a weeka score needs 7 daily checks: 6 so far
• What an agent can do with it1 of 3 use cases
• Answeredmeasuring6 of the 7 daily checks it takes to print a share
• Median first answer301 ms
• Space in an agent's context≈ 910 tokensthe definitions of all its tools (5), which an agent carries on every turn
• Tool definitionsA · 100 of 100
• Typed results5 of 5 toolsdeclared outputSchema: results come typed, read once

• Every tool passes all six checks.

A program checks the server once a day: initialize and tools/list, no model. Tokens are the definitions' length at about four characters a token. The grade averages six checks of every tool's name, description, schema and annotations; it says how well the tools are described, not whether they work. The score weighs what was measured and nothing else: answering (25%), doing the product's job (25%), definitions (20%), context (10%), use (10%) and how readily a client connects (10%). A part that was not measured is left out, and a hidden instruction caps the score at 40. The state of vendors' MCP servers: method and numbers →

• find_esim_plans

  Lists Inbox eSIM data plans for a destination (country, city, region such as Europe, or 'global'), cheapest first, with plan_id, data in GB, validity in days and price in USD. Data only, no phone number; works on unlocked eSIM phones.

• buy_esim

  Starts the purchase of one eSIM plan for the customer and returns a payment link. Pay it with the Machine Payments Protocol (HTTP 402, Stripe shared payment token) to complete the order. Before calling, confirm the plan, the price and the…

• make_esim_cart

  For a trip to several countries (or several phones): turns 2 to 6 plan_ids from find_esim_plans into one cart link. The customer opens it, checks the eSIMs and pays once on Stripe; each eSIM comes in its own QR email and can be refunded…

• check_esim_device

  Says whether a phone model is likely to take an eSIM (likely, unlikely or check), from the model name, with how to be sure on the phone itself. Call it before buy_esim when the customer is unsure.

• get_order_status

  Where an Inbox eSIM order is (awaiting_payment, preparing, ready_to_install, installed, in_use, ended, refunded, cancelled, with_support), with data used, the end date and the order page. Needs the order number and the email it was bought…