mcp-better

mcp-better — built for 7/28

NONE | GOOD | [BETTER] | BEST

Textbook for AGENTS.md on that scale — honest modern MCP at the BETTER step.
(protocol 2026-07-28 — the modern MCP release)

the book is the app is the book

AAIF-verified modern MCP textbook that runs. Rust · rmcp 3.0.x (lock 3.0.1, Tier 1 assessed) · Discover · stamped list cache.
Book: textbook/ — what · why · how · doctrine.
App: this binary + smokes. Lesson after lesson, version after version — knowledge compounds.

BEST (persistent project DNA for agents — AGENTS.md / FAF at scale) lives at faf.one/agents — one hop up from this textbook.

Dual-package (optional)

Cargo stays first. Optional npm is only an on-ramp to the same native binary for npx-style hosts.

→ Why dual-package — positioning + FAQ
→ Full guide (how) — lockstep, publish order, OIDC, score + wire

Skills over MCP (optional · textbook)

One Agent Skill (mcp-better-lab) on the same process as tools:

→ docs/SKILLS-OVER-MCP.md — extension · skills/list · skills/get · digests

What is 7/28?

Name	What it is
7/28	The era name — speakable, brandable. “Built for 7/28.”
2026-07-28	The protocol version — the date string on the wire / in SDKs.

7/28 is a great name. 2026-07-28 is a date.
Humans say 7/28. Machines negotiate 2026-07-28.

What to expect

• Built for 7/28 — not bolted onto a legacy server (official rmcp 3.0.x / Tier-1 assessed cut).
• Honest surface — transport and capabilities match docs and CI.
• Roadmap expands the era — versions add road; they do not “become” 7/28 later.

Version	Lesson (the version is the lesson)
v0.1	7/28 over stdio — Discover, stamped ttlMs / cacheScope, stable order, health + echo
v0.2	Same 7/28 era + Streamable HTTP road + routing headers (Mcp-Method / Mcp-Name)
v0.3	Same era + deeper correctness — multi-list + restart-order smokes · mcp-worse contrast
v0.4	Same era + dual package — cargo + npm shim · npx mcp-better with no Rust toolchain
v0.4.3	Same era + confirm_echo MRTR (SEP-2322) + Agent Skills (mcp-better-lab) — see docs/MRTR-CONFIRM-ECHO.md · docs/SKILLS-OVER-MCP.md
v0.4.4	Same era + book matches 0.4.3 wire — no new tool · catalogs named health → echo → confirm_echo
v0.5	Same era + matching client completes MRTR — mrtr-client finishes confirm_echo

What BETTER means

• Protocol honesty — claim 7/28 / 2026-07-28 only for surfaces you implement and test.
• Discover-compatible — clients should use ClientLifecycleMode::Discover (or Auto → 7/28), not only legacy initialize.
• List cache stamps — tools/list returns positive ttlMs and cacheScope (static catalog → public). SDK defaults are unstamped.
• Stable tool order — same process, same order across N list calls.
• Transports — stdio (default) and Streamable HTTP (--http) in the same 7/28 era.

Quickstart (≤10 min)

Zero Rust — npm / npx (v0.4+)

# No Rust toolchain required. Downloads the native binary from GitHub Releases.
npx mcp-better --help
npx mcp-better
# hosts: point stdio command at `npx` / `mcp-better` from the npm package

From source / crates.io (Rust 1.85+)

git clone https://github.com/Wolfe-Jam/mcp-better.git
cd mcp-better
cargo build --bins
cargo test
cargo run --example stdio-client
# louder 0.3 smokes (build --bins first; or: bash scripts/ci.sh)
MCP_BETTER_BIN="$(pwd)/target/debug/mcp-better" cargo run --example order-restart-smoke
MCP_BETTER_BIN="$(pwd)/target/debug/mcp-better" \
  MCP_WORSE_BIN="$(pwd)/target/debug/mcp-worse" \
  cargo run --example contrast-smoke
MCP_BETTER_BIN="$(pwd)/target/debug/mcp-better" cargo run --example http-smoke
# 0.5 matching client (completes confirm_echo)
MCP_BETTER_BIN="$(pwd)/target/debug/mcp-better" cargo run --example mrtr-client

stdio (default — Cursor / Claude Desktop):

cargo run --release
# or from crates.io:
cargo install mcp-better --version 0.4.3
mcp-better --help
# optional lying companion (teaching only — not for hosts):
# cargo install mcp-better --version 0.4.3 --bin mcp-worse
# this tree is 0.5.0 (matching client). Registries stay 0.4.3 until tagged.

First cargo install compiles the ecosystem once (not 100+ of our tools — just Rust deps). One-time wait; then you’re done.
Prefer no compile? Use npx mcp-better (npm shim).

Streamable HTTP (local demo only — see SECURITY.md):

cargo run --release -- --http
# http://127.0.0.1:8787/mcp
# MCP_BETTER_HTTP_ADDR=127.0.0.1:9000 mcp-better --http

Transport selection (CLI wins over env):

How	Value
CLI	mcp-better (stdio) · mcp-better --http · mcp-better --stdio
Bare args	http / stdio (same meaning as flags)
Env	MCP_TRANSPORT or MCP_BETTER_TRANSPORT → stdio | http (MCP_TRANSPORT first if both set)
HTTP bind	MCP_BETTER_HTTP_ADDR — default 127.0.0.1:8787. Do not use 0.0.0.0 unless you accept an unauthenticated open endpoint.

Tools

Tool	Purpose
health	Liveness — status, version, protocol. No side effects. Not a k8s probe contract.
echo	Pure demo — returns message unchanged.
confirm_echo	Textbook MRTR (SEP-2322) — echo after mid-call confirm · sealed requestState.

Protocol claims (v0.5.0 — same 7/28 era · matching client completes MRTR)

Surface	Status
Era / protocol	7/28 · negotiated 2026-07-28 (Discover preferred)
Transport	stdio (default) · Streamable HTTP (--http)
HTTP mode	Stateless for 7/28 · json_response · local Host guards
Routing headers	Streamable HTTP POSTs use Mcp-Method and Mcp-Name when naming a tool (SEP-2243); http-smoke asserts this happy path
Capabilities	tools · resources (skill docs) · experimental skills extension
List cache	ttlMs=60000, cacheScope=public, order health→echo→confirm_echo (restart-stable)
MRTR (optional)	confirm_echo — mid-call confirm · sealed requestState · matching client mrtr-client · docs/MRTR-CONFIRM-ECHO.md
Skills (optional)	mcp-better-lab · skills/list · digests · docs/SKILLS-OVER-MCP.md
Lying companion	mcp-worse — unstamped + reversed order (contrast-smoke only)
OAuth / tasks	out of hero

Textbook

The book is the app is the book — textbook/ (Season 1 · doctrine).

Start: textbook/README.md → lab Ch 09.

Non-goals (GOOD-era habits we refuse)

• Shipping unstamped list results while claiming 7/28 modernity
• Requiring project.faf or any BEST tooling on this repo’s main branch
• Treating stdio as “not real 7/28” — stdio is a first-class 7/28 transport
• FAF install tax in the AAIF lede — this repo is protocol textbook, not a FAF product

Registry identity

• MCP Registry name: mcp-name: io.github.Wolfe-Jam/mcp-better
• Dual packages (same version, both stdio):
  • registryType: cargo · identifier: mcp-better · crates.io
  • registryType: npm · identifier: mcp-better · registry.npmjs.org
    (Node shim downloads the native binary from GitHub Releases — no Rust on the host)
• Package transport in server.json is stdio only — by design.
  Hosts spawn via cargo install / npx mcp-better on stdio.
  Streamable HTTP (--http) is an opt-in local demo in the same binary and the same 7/28 era; it is not a Registry remote package. Discover it in this README and --help.

See server.json. Not one.faf/*.

Publish

Ship process: /pubbetter (skill) · short form docs/PUBBETTER.md · local ship bar:

export PATH="$HOME/.cargo/bin:$PATH"
bash scripts/ci.sh

BEST

For persistent, versionable AI project context beyond a protocol textbook:

https://faf.one/agents

Docs

• BETTER.md — ladder + claim surface
• docs/BETTER-BEST.md — BETTER vs BEST
• GETTING-STARTED.md
• docs/SDK-NOTES.md — serve vs Discover honesty
• docs/DUAL-PACKAGE-FOR-RUST-MCP.md — why dual-package (cargo first · FAQ)
• docs/DUAL-PACKAGE-RUST-MCP.md — how: full dual cargo+npm guide
• docs/MCP-DIST-POST.md — lockstep post-step (does not publish)
• SECURITY.md · CONTRIBUTING.md

License

MIT — see LICENSE.