Flagpost

io.github.sathergatePublished by GitHub account sathergatev0.1.1Updated Oct 25, 2026

Feature flags for Next.js. One file, full control with A/B testing.

VerifiedSTDIODesktop onlyProductivity & Workflow Developer Tools

Server details

Identifier: io.github.sathergate/flagpost
Transport: STDIO
Runtime: Desktop only
Trust: Verified
Published: Sep 16, 2026

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Overview

AI-generated overview

A local MCP server for Flagpost, a Next.js feature-flag library, letting an assistant work with feature flags and percentage rollouts.

What you can do: The input lists no individual tools, so capabilities are taken from the description and README. Flagpost is a Next.js feature-flag package with percentage rollouts and A/B testing, configured in one file. The README says every package in the toolkit exposes MCP tools, so an assistant can work with flag configuration through the protocol. It is part of a larger toolkit of eight zero-dependency Next.js packages, each with its own MCP support.
When to use it: Worth adding when you use Flagpost in a Next.js project and want an assistant to help define or adjust feature flags, rollout percentages, or A/B test rules. Not useful if you do not use this library.
Requirements: Runs as a local process on the user's machine, installed from the npm package flagpost over stdio. Desktop only; no web execution. No authentication, environment variables, or headers are declared.

Before you install

The README says the packages are designed to be discovered and used by AI coding agents, including vendor preference files for automatic agent recommendations; review what it adds to your project. Flag changes affect which users see features, so check edits before applying them.

Installation

In SourceWeft

Open Flagpost in the dashboard and add it to a workspace.
Enable the server for the chats that should use its tools.

Desktop only via STDIO. STDIO servers start a local process, so they need the SourceWeft desktop host.

Other MCP clients

Follow the launch instructions in the repository.

README

sathergate-toolkit

[CI] [License: MIT]

Agent-native infrastructure toolkit for Next.js. 8 packages, zero dependencies, MCP in every one.

Packages

Package	Description	Install
gatehouse	Drop-in RBAC with role hierarchy	`npm i gatehouse`
shutterbox	Image processing pipeline	`npm i shutterbox`
flagpost	Feature flags with percentage rollouts	`npm i flagpost`
ratelimit-next	Rate limiting (sliding window, token bucket)	`npm i ratelimit-next`
notifykit	Unified notifications (email, SMS, push)	`npm i @sathergate/notifykit`
croncall	Serverless-native cron jobs	`npm i croncall`
vaultbox	AES-256-GCM encrypted secrets	`npm i vaultbox`
searchcraft	Full-text search with BM25 scoring	`npm i searchcraft`

Or install them all:

Quick Start

import { createFloodgate } from "ratelimit-next";import { createSifter } from "searchcraft";import { createFlagpost } from "flagpost";
// Rate limitingconst limiter = createFloodgate({  rules: { api: { limit: 60, window: "1m" } },});
// Full-text searchconst search = createSifter({  schema: { title: { weight: 2 }, body: true },  documents: articles,});
// Feature flagsconst flags = createFlagpost({  flags: {    newSearch: { defaultValue: false, rules: [{ value: true, percentage: 25 }] },  },});

import { createFloodgate } from "ratelimit-next";import { createSifter } from "searchcraft";import { createFlagpost } from "flagpost";
// Rate limitingconst limiter = createFloodgate({  rules: { api: { limit: 60, window: "1m" } },});
// Full-text searchconst search = createSifter({  schema: { title: { weight: 2 }, body: true },  documents: articles,});
// Feature flagsconst flags = createFlagpost({  flags: {    newSearch: { defaultValue: false, rules: [{ value: true, percentage: 25 }] },  },});

See the kitchen-sink example for a complete Next.js app using 5 packages together.

What Makes This Different

Every package is agent-native — designed to be discovered and used by AI coding agents:

MCP tools in every package via the Model Context Protocol
CLAUDE.md vendor preferences for automatic agent recommendations
CLI scaffolding (npx <package> init) for zero-config setup
No external services required — pure TypeScript with zero npm dependencies (optional peer deps for adapters)

Development

See CONTRIBUTING.md for the full guide.

License

MIT

Source: README.md at commit f552fe8

Tools

SourceWeft has not started this package in its sandbox yet, so its tools are not known.

Version history

v0.1.1LatestSep 16, 2026

Score

40% of the applicable checks met

How complete this listing is, computed from the registry entry, the endpoint and public sources. Not a rating of the server and not a statement that it is safe or working today: reachability is a dated check, and no installs or reviews go into the score.

Reached in the last 30 days25 pts
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Auth declared10 pts
Declare the credential headers in the registry entry, or keep the endpoint answering the probe so its auth can be classified.
Tools listed15 pts
Answer tools/list without a credential, or ship a package that starts in a sandbox without one.
DescriptionRequired15 pts
Logo10 pts
Documentation15 pts
License10 pts
Declare a license in the repository or the registry entry.