Delulu - A suite of MCP tools to supercharge your LLM skillset

Delulu provides a suite of CLI tools and MCP (Model Context Protocol) servers to help your LLM search, crawl, and extract high-quality information from the web and academic sources.

Available Tools

Motivation

Screenshots

Features

• 🪄 MCP Server: Works with stdio transport (Claude Desktop) and HTTP transport
• 💻 CLI Tools: Direct flights and hotels commands
• 🚦 Rate Limiting: Let's be good citizens.
• 🍪 Cookie Management: Let's be crafty citizens.
• 📦 Prebuilt Binary: delulu-all-mcp for Windows/macOS/Linux × x86-64/arm64, for those allergic to Docker
• 🐳 Container Ready: Docker, Podman and Docker-Compose support with prebuilt image
• 🚀 High Performance: Built with Rust, Axum, and Tokio
• ☁️ Lightweight: No browser, Selenium, or Playwright - direct queries via reverse-engineered Protobuf

Prebuilt release: v0.2.0 ships a single prebuilt binary, delulu-all-mcp, which bundles all 21 tools (travel, webfetch, websearch, arXiv/IACR/PubMed papers, mcpify). The individual apps are built from source with cargo — see Building from source.

Installation

📦 Option 1: Prebuilt Binary

A single delulu-all-mcp binary is published for Windows, macOS and Linux (x86-64 and arm64). It bundles all 21 tools; the individual apps are built from source (Option 2 below).

The archives below are published with the v0.2.0 release (see Releases); until that tag exists, build from source.

1. Quick Install - Platform-specific one-liners:

Invoke-WebRequest -Uri "https://github.com/mratsim/delulu/releases/latest/download/delulu-all-mcp-windows-x86_64.zip" -OutFile "delulu.zip"; Expand-Archive -Path "delulu.zip" -DestinationPath "."; Remove-Item "delulu.zip"

Invoke-WebRequest -Uri "https://github.com/mratsim/delulu/releases/latest/download/delulu-all-mcp-windows-arm64.zip" -OutFile "delulu.zip"; Expand-Archive -Path "delulu.zip" -DestinationPath "."; Remove-Item "delulu.zip"

curl -sL "https://github.com/mratsim/delulu/releases/latest/download/delulu-all-mcp-macos-arm64.tar.gz" | tar -xz

curl -sL "https://github.com/mratsim/delulu/releases/latest/download/delulu-all-mcp-linux-x86_64.tar.gz" | tar -xz

curl -sL "https://github.com/mratsim/delulu/releases/latest/download/delulu-all-mcp-linux-arm64.tar.gz" | tar -xz

2. Manual Download - Visit the GitHub Releases page and download the archive for your platform and architecture, then extract it (it contains the delulu-all-mcp binary — .exe on Windows).

3. Set up your MCP client - see Usage below for the stdio/HTTP transports and Claude Desktop config.

Why only one binary? Building every app for x86-64/arm64 × Windows/macOS/Linux would produce dozens of artifacts that confuse more than they help. The individual apps are one cargo build away (Option 2) and delulu-all-mcp gives you all 21 tools from a single binary.

🦀 Option 2: Cargo (Rust Users)

Every app is a normal Cargo package in this workspace. cargo install puts the binary in ~/.cargo/bin/; cargo build --release leaves it in ./target/release/.

git clone https://github.com/mratsim/delulu
cd delulu

# Build everything (all apps, all binaries):
cargo build --release

# Or install one app — e.g. the unified all-mcp server (all 21 tools):
cargo install --path delulu-apps/all-mcp --features mcp

Individual apps:

For one app (e.g. the travel MCP server):

cargo install --path delulu-apps/travel-search --features mcp
# binaries: ~/.cargo/bin/delulu-travel-mcp (plus delulu-flights / delulu-hotels)

--features mcp builds the MCP server binary; the CLI-only binaries are built by default when the feature is omitted. The default mcp feature set works on Linux, macOS and Windows.

🐳 Option 3: Docker / Podman

A prebuilt OCI image is published on GitHub Container Registry (GHCR):

• ghcr.io/mratsim/delulu/all-mcp (unified all-mcp server, all 21 tools)

# HTTP transport (for remote clients) — NO built-in authentication!
# Put it behind a TLS-terminating reverse proxy that enforces auth
# (mTLS or bearer token), or restrict the port with a firewall.
docker run -p 8080:8080 \
  --env RUST_LOG=info \
  ghcr.io/mratsim/delulu/all-mcp:latest \
  http --host 0.0.0.0 --port 8080

# Stdio transport (for Claude Desktop) - requires interactive mode `docker run -i --rm`
docker run -i --rm ghcr.io/mratsim/delulu/all-mcp:latest stdio

To build the image from source:

docker build --target delulu-all-mcp-runtime -t delulu-all-mcp .
docker run -i --rm delulu-all-mcp stdio

🐳 Option 4: Docker Compose

There is a sample docker-compose.yml that builds and runs the travel MCP server from source over HTTP. delulu-all-mcp is not in the compose file — it ships as a standalone binary or OCI image (Options 1/3).

git clone https://github.com/mratsim/delulu
cd delulu
docker-compose up -d
# The compose server listens on http://localhost:8080/mcp

Usage / Tool reference

Available tools (21)

All MCP servers share the same client-facing tool names; delulu-all-mcp re-exports the full union:

webfetch:        webfetch, webfetch_raw, fetch_doc
websearch:       web_search, web_search_next_page
travel:          search_flights, search_hotels
arxiv:           arxiv_search_papers, arxiv_get_papers_by_id, arxiv_get_paper
iacr:            iacr_list_recent_papers, iacr_get_paper_details, iacr_paper_pdf_url, iacr_get_paper
pubmed:          pubmed_search, pubmed_get_summaries, pubmed_fetch_abstracts, pubmed_find_related, pubmed_get_database_info, pubmed_match_citation, pubmed_get_paper

That is 21 tools. Every paper tool is namespaced by repository prefix (arxiv_*, iacr_*, pubmed_*) because the three paper servers are separate repositories with overlapping vocabulary (papers, ids, details, abstracts, citations) — the name alone tells the caller which repository it talks to. The standalone per-package binaries keep their unprefixed names.

CLI transport

delulu-* binaries run two transports — stdio (Claude Desktop) and HTTP:

# CLI transport (Claude Desktop-friendly):
delulu-all-mcp stdio

# HTTP transport (for remote clients) — NO built-in authentication!
# Put it behind a TLS-terminating reverse proxy with auth, or a firewall.
delulu-all-mcp http --host 0.0.0.0 --port 8080

The same two transports apply to every individual delulu-* binary built from source (e.g. delulu-travel-mcp stdio).

For delulu-all-mcp the same flags apply plus the rate/API-base overrides (see below).

delulu-all-mcp — unified 21-tool MCP server

delulu-all-mcp is a single binary that hosts all 21 tools from every app behind one shared RateLimitedCrawler. A single GCRA bucket per domain is shared across webfetch, websearch, travel, and the three paper apps, so one app hammering a host limits every other app that touches the same host.

Merged CLI flags

• --qps <u32> — queries per second for the shared crawler (default 1, 1..=10000)
• --burst <u32> — burst size for the shared crawler (default 1)
• --max-resp-size-mb <u32> — per-response size cap in MB (default 50, 1..=1024)
• --arxiv-api-base-url <url> — override the arXiv API base URL (default https://export.arxiv.org/api/query)
• --iacr-api-base-url <url> — override the IACR eprint API base URL (default https://eprint.iacr.org)
• --pubmed-api-base-url <url> — override the PubMed E-utilities base URL
• --expose-local-networks — allow webfetch tools to reach local/private networks (default off)

--expose-local-networks affects ONLY the webfetch tools (webfetch, webfetch_raw, fetch_doc). The paper-search and websearch tools do not use it.

Rate policy (full delta table)

Because all-mcp merges six apps behind one crawler, the per-domain rate policy is shared; here is the full standalone-vs-all-mcp delta (qps, burst, timeout, cap, HTTP/2, redirects): The default is qps=1 / burst=1 — a conservative single-DOMAIN-at-a-time throttle that costs latency but is the least likely to get your IP throttled. See the deltas below.

Caution (tradeoff sentences, read before pointing an LLM at this):

1. per-domain qps is reduced for 5 of 7 engine configs (webfetch/brave/travel/iacr/pubmed 2/2/2/3/3 → 1) in exchange for one per-domain bucket shared across all tools;
2. timeouts are relaxed for travel (5 s → 30 s) and websearch (10 s → 30 s) — a hung upstream now delays up to 30 s;
3. body caps: search 5 MB → 50 MB (oversized responses that errored standalone now succeed — different error semantics), travel/papers gain a 50 MB cap; enforcement caveat: the cap is enforced via Content-Length pre-check plus per-tool streaming caps where they exist; chunked responses without Content-Length are not hard-capped; webfetch tools are fixed at the lib's 50 MB regardless of the --max-resp-size-mb flag;
4. the domain cache is an LRU with max_domains = 128 keyed on host only (port/scheme ignored); eviction resets the evicted domain's GCRA state to a fresh burst, and the 128-slot cache is now shared across 6 apps — roughly 6× shorter per-domain state lifetime;
5. --burst=1 therefore serializes concurrent calls to the same host at qps spacing;
6. the GCRA queue wait is unbounded and sits outside the 30 s request timeout; worst case at qps=1 a retrying call can stall a host for tens of seconds;
7. --qps, --burst, --max-resp-size-mb overrides exist if you want to relax or tighten the shared policy;
8. HTTP/2 requests are sent on the shared crawler (where the engine supports it) — see the http2 column;
9. travel redirect delta: travel tools follow max 5 redirects in all-mcp, vs 10 standalone — this is documented, not "fixed", to avoid creating a webfetch/paper mismatch;
10. the session cache is shared across all clients (512 sessions / 10 min) — heavy concurrent pagination may evict other sessions early.

Claude Desktop configuration (stdio)

Add the block to your claude_desktop_config.json — stdio, exactly:

{
  "mcpServers": {
    "delulu-all-mcp": {
      "command": "delulu-all-mcp",
      "args": ["--qps", "1", "--burst", "1", "--max-resp-size-mb", "50", "stdio"]
    }
  }
}

Do not add --expose-local-networks unless your documents are on the same machine/private network. It silently widens the SSRF surface for the webfetch tools.

For the HTTP transport (no auth built-in):

delulu-all-mcp http --host 127.0.0.1 --port 8080
# NO authentication — bind to 127.0.0.1 (or a firewall) and do not expose the port publicly.

Docker Compose: delulu-all-mcp is not yet wired into docker-compose.yml — run it from the binary or OCI image directly for now.

License

Licensed under the GNU Affero General Public License v3.0 (AGPL-3.0).

This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

See LICENSE or http://www.gnu.org/licenses/ for details.