Jevcore MCP vs Variflight MCP
A side-by-side look at the Jevcore MCP and Variflight MCP MCP servers: transport, auth, tools, quality signals, and the config to install either one in Claude, Cursor, Windsurf or VS Code.
Verdict: choose Jevcore MCP for developer tools work as a local process; choose Variflight MCP for developer tools as a local process. You can also run both side by side in one mcpServers block.
Which MCP server should you choose?
Choose Jevcore MCP when
- You need dedicated capabilities in the Developer Tools domain.
- You prefer a local stdio subprocess transport.
- You want tools like
jev_ask, jev_rank, jev_check.
Choose Variflight MCP when
- You need dedicated capabilities in the Developer Tools domain.
- You prefer a local stdio subprocess transport.
- You have the keys it needs:
VARIFLIGHT_API_KEY. - You want tools like
searchFlightsByDepArr, searchFlightsByNumber, getFlightTransferInfo.
Feature & specification comparison
Rows where the two servers differ are marked.
| Spec | ||
|---|---|---|
| Category | Developer Tools | Developer Tools |
| Quality signal | 67/100 · Great | 67/100 · Great |
| Install command | Confirmed | Confirmed |
| Transport | Local subprocess (stdio) | Local subprocess (stdio) |
| Auth | Not declared | Not declared |
| Pricing | Free | Not declared |
| Required env vars | None listed | VARIFLIGHT_API_KEY |
| Verified owner | Community listing | Community listing |
| GitHub stars | 102 | 33 |
| Directory activity | 1 views 0 installs 0 upvotes | 0 views 0 installs 0 upvotes |
| Tools | 3 | 9 |
| Full listing | View Jevcore MCP | View Variflight MCP |
Tools & capabilities
Jevcore MCP tools 3
jev_askAsk TypeSafe Jev one or more typed questions about a single piece of state. Jev does not generate text: it returns a selected option and calibrated probabilities. Use it for judgments the rest of the work branches on — routing, classifying, scoring, triaging. Do NOT use it to write prose, explain, summarize, or generate code. Question types: "noul" is yes/no and returns the probability of true; "choice" picks one of the criteria keys you declare; "score" places the state on an ordered scale whose levels you declare in ascending order. A noul may also declare "boundary" — what true means and what false means — which is worth supplying whenever the line between them is not obvious. Batch related questions into one call: they are answered against the same state in one round-trip. A score question answers with a numeric "score" that may fall between levels, a "legend" mapping each level index to its description, and probabilities per level. This tool returns probabilities, not decisions — apply your own confidence threshold before acting, and treat a low-confidence answer as unknown rather than picking for it.jev_rankRank a list of candidates by how well each satisfies one stated criterion. Returns every candidate with an independent relevance probability, sorted. Use it to order search hits, triage a backlog, or find the one item that answers a question. The probabilities are independent per-candidate judgments, NOT a distribution that sums to 1. A flat set of scores means "none of these stands out", not a fine-grained ordering. What you send is capped, and the two caps behave differently. The candidate list is truncated at 16,000 characters, and the reply carries `truncated: true` when that happens — check for it, because a cut list is still ranked and the scores then describe what Jev actually read rather than what you sent. The generated questions are refused at 4,000 characters instead: exceeding that gives you an error asking for fewer or smaller items, never a silent best-N, so retrying the same call cannot help. Because the criterion is repeated into every candidate's question, that second cap is what bounds the candidate count — measured, an ordinary criterion fits 20 candidates and a 400-character criterion fits 7, while candidate length does not change the count at all and only starts truncating the list past roughly 1,600 characters per candidate.jev_checkCheck whether a piece of evidence supports a specific claim. Returns "supported", "contradicted", "conflicted", "insufficient", or "unknown", with the underlying probabilities. The distinction between "not supported" and "contradicted" is the reason to use this rather than reading the evidence yourself. It judges one claim against the evidence you give it. It does not search for evidence, and it cannot detect that you omitted the decisive passage.
Variflight MCP tools 9
searchFlightsByDepArrSearch direct flights by departure and arrival location plus date. Use depcity and arrcity when the user specifies cities such as BJS or SHA. Use dep and arr when the user specifies exact airports such as PEK or PVG. Provide one departure field and one arrival field, and do not mix city and airport codes for the same side. All codes must be valid IATA 3-letter codes. Date must be in YYYY-MM-DD format. For today's date, use getTodayDate instead of hardcoding.searchFlightsByNumberSearch a flight by flight number and date. The flight number must include the airline code, for example MU2157 or CZ3969. dep and arr are optional and should only be provided when the exact airports are known. Date must be in YYYY-MM-DD format. For today's date, use getTodayDate instead of hardcoding.getFlightTransferInfoSearch connecting flight options between a departure city and an arrival city on a specific date. Use city IATA 3-letter codes such as BJS, SHA, or LAX. This tool is for transfer or connection itineraries between cities, not for airport weather, airport facilities, or realtime tracking. Date must be in YYYY-MM-DD format. For today's date, use getTodayDate instead of hardcoding.flightHappinessIndexUse this tool when the user wants comfort-focused details for a known flight, such as punctuality, aircraft type, cabin configuration, seat comfort, meals, entertainment, or other onboard experience details. This tool works best when a specific flight number and date are already known. Do not use it for fare search, itinerary recommendation, or raw price comparison.getRealtimeLocationByAnumGet realtime flight location by aircraft registration number, also called tail number, such as B2021 or B2022. Use this only when the aircraft registration number is known. If the registration number is unknown, first try to find the flight through searchFlightsByNumber and then use the aircraft registration number from that result.getTodayDateGet today's date in local timezone (YYYY-MM-DD format). Use this tool whenever you need today's date - NEVER hardcode dates.getFutureWeatherByAirportGet the 3-day airport weather forecast for today, tomorrow, and the day after tomorrow by airport IATA 3-letter code, such as PEK, SHA, CAN, or HFE.searchFlightItinerariesUse this tool when the user wants a concise recommended itinerary summary in natural language. It returns a text-style result that summarizes how many sale flights match, the overall lowest price, the shortest duration, and several recommended options. Use city IATA 3-letter codes only. If the user instead needs structured raw flight pricing data with each flight and cabin price, use getFlightPriceByCities.getFlightPriceByCitiesUse this tool when the user needs structured raw pricing data. It returns sale flights between two cities as a list of flights, and each flight contains cabin entries with prices. This is better than searchFlightItineraries when the caller needs per-flight, per-cabin price details instead of a natural-language recommendation summary. All city codes must be valid IATA 3-letter codes (e.g. BJS for Beijing, SHA for Shanghai, CAN for Guangzhou, HFE for Hefei).
Ready-to-paste client configs
Paste either block (or both) into your client config, e.g. claude_desktop_config.json or ~/.cursor/mcp.json. We only show a config when the install command is confirmed.
Jevcore MCP
{
"mcpServers": {
"jevcore-mcp": {
"command": "npx",
"args": [
"-y",
"jevcore-mcp"
]
}
}
}
Variflight MCP
{
"mcpServers": {
"variflight-mcp": {
"command": "npx",
"args": [
"-y",
"@variflight-ai/variflight-mcp"
],
"env": {
"VARIFLIGHT_API_KEY": "YOUR_VARIFLIGHT_API_KEY_HERE"
}
}
}
}
Frequently asked questions
Jevcore MCP is categorized under Developer Tools and uses a local stdio subprocess. Variflight MCP belongs to Developer Tools and uses a local stdio subprocess. Pick Jevcore MCP for developer tools work and Variflight MCP for developer tools.
Copy the mcpServers block from the config section on this page into your client's config (for example claude_desktop_config.json or ~/.cursor/mcp.json), then fully restart the client.
Jevcore MCP is listed as free. Variflight MCP has no declared pricing — check the project's own site. If a server needs environment variables such as API keys, define them under the env key in your client's MCP config.
Yes. MCP clients support multiple servers: add jevcore-mcp and variflight-mcp as separate keys in the same mcpServers object, and your assistant will call tools from either one.
On AllMCPs, Jevcore MCP has a quality signal of 67/100 (Great) with 1 views, 0 installs and 102 GitHub stars. Variflight MCP has 67/100 (Great) with 0 views, 0 installs and 33 GitHub stars.