esimdata MCP server

• Registry nameapp.esimdata/esimdataverified in the MCP registry

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

• Stateanswerschecked 2026-10-29
• Tools6
• Server calls itselfesimdata
• Server version0.1.0
• Protocol version2025-06-18

On 2026-10-29 the server answered initialize and tools/list without a sign-in. First answer in 59 ms.

• Its tools do every use case we checked: compare travel eSIM plans by price for a country; check whether your phone supports eSIM; find the cheapest plan with 5 GB for a week abroad.
• 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 it3 of 3 use cases
• Answeredmeasuring6 of the 7 daily checks it takes to print a share
• Median first answer116 ms
• Space in an agent's context≈ 900 tokensthe definitions of all its tools (6), which an agent carries on every turn
• Tool definitionsA · 97 of 100
• Typed results0 of 6 toolsdeclared outputSchema: results come typed, read once

• Parameters without a description: in 1 of 6

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 →

• search_plans

  Find travel eSIM data plans for a destination from every provider esimdata tracks, ranked neutrally by price (or price per GB, or validity). Filter by trip length, data, unlimited, needs (hotspot, 5G, phone number, top-up, no ID check)…

• get_plan

  Everything esimdata knows about one plan (by the id search_plans returned): all countries it covers, networks, policies, the provider's own page, the buy link and its price history.

• compare_plans

  Put 2 to 10 plans (ids from search_plans) side by side with the same fields, in the order given, to help a traveller choose.

• country_overview

  A destination at a glance: how many plans and providers, the cheapest plan, the cheapest per GB, and which mobile networks the providers say they use there.

• check_phone

  Check whether a phone, tablet or watch model supports eSIM, from the manufacturer's own published list (with regional exceptions, e.g. models sold in mainland China), with the source link.

• list_providers

  Every eSIM provider esimdata compares, with its website and whether esimdata earns a commission when a traveller buys through it (ranking never depends on it).