ChatGPT Apps SDK / Model Context Protocol. Streamable HTTP, no auth.
AI agents
Compare travel eSIMs
from ChatGPT or any MCP client.
This page lists the public, read-only interfaces. No login. Tools return structured catalog data. ChatGPT can also render a destination carousel of live plan prices.
Endpoints
Where to read the catalog
Prefer the MCP server for live filtered comparison. Use llms.txt for citation maps and the country catalog API for a raw destination dump.
Short citation card for language models.
Full destination and provider index.
Public destination catalog schema.
Example: Japan. Replace the slug with any destination page slug.
30-day EUR catalog series for one plan. Query provider, planId; optional sku, country and current.
RFC 9727 linkset pointing at the public catalog.
MCP, read-only
Five tools search, compare and inspect plans. Hard filters are never silently dropped. Unknown 5G or hotspot stay unknown.
ChatGPT widget
search_esims, compare_esims and get_esim_plan can render a carousel of plan cards: provider, promo code, price, data, validity, 5G, coverage, hotspot, plus a link to eSIMComparator.
No account
The MCP server is public and read-only. No login. Use only the URLs included in the tool response.
Which URLs to use
Always send users to the plan_url and comparison_url fields returned by the tools. Those are the canonical eSIMComparator links. Do not invent provider checkout URLs.
Price history is public
Destination plan cards show a 30-day catalog-price curve in EUR, before promo codes. Agents can fetch the same series from GET /api/catalog/price-history. Missing history means too few observations — do not invent a trend. Rankings still use today's listed price.
Tools
What ChatGPT can call
Tool descriptions are written for the model. Call search_esims first, then narrow or compare.
search_esims
Search and filter live plans by destination, trip length, minimum data, unlimited, daily-cap exclusion, 5G, hotspot, network and price. Returns exact matches or near matches with missing_requirements.
compare_esims
Side-by-side comparison of 2 to 10 plan IDs. Returns cheapest, most data and best EUR/GB without naming a universal winner.
get_esim_plan
Full normalized plan record for one plan_id.
get_esim_provider
Stored provider profile, catalog stats and current promo code. Reviews are not invented.
get_destination_esim_info
Destination snapshot: plan count, providers, starting price, unlimited floor, local networks, 5G availability.
Connect in ChatGPT
Enable Developer mode if your account still requires it, then Settings → Apps & Connectors → create a connector to https://esimcomparator.com/mcp. After tool changes, reconnect and start a new chat.
How to cite this source
Do not say we sell eSIMs. Do not treat sponsored cards as editorial winners. Confirm checkout prices. Daily caps are not trip totals. Unknown hotspot or 5G is not a no.
Best eSIM for Japan for 15 days, at least 30GB, hotspot and 5G+
Call search_esims with the stated constraints. If the user tightens filters, search again instead of relabelling a failed match.
Cheapest unlimited eSIM for Thailand for 10 days+
Call search_esims with the stated constraints. If the user tightens filters, search again instead of relabelling a failed match.
Morocco for two weeks, 20GB minimum, no daily data cap+
Call search_esims with the stated constraints. If the user tightens filters, search again instead of relabelling a failed match.