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Explicit Formula — Second Brain

by travisbergen2version 0.1.0i★ –iRuns on your computer
Registry nameio.github.travisbergen2/second-brain

Install

Overview

Description from the maker (original English)

Your own notes, searched and cited by your AI — local-only, allowlist-gated, capped, and logged.

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

  • Connection: Runs on your computer
  • Transport: stdio
  • Category: Docs, sheets & office work

Install

Pick the AI app you use, then copy the settings.

Before you install

  • Basic checks: 1 of 1 passed
  • Runs on your computer with your user’s permissions (files, network, apps).
  • The registry lists no key to fill in.

You need

  • npmNode.js installed (for the npx command)

Which app do you use?

Pick your app above. We remember it, so next time the button says “Install in …”.

Open Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json

{
  "mcpServers": {
    "second-brain": {
      "command": "npx",
      "args": [
        "-y",
        "@travisbergen2/second-brain-mcp",
        "--vault"
      ]
    }
  }
}

Run this in your terminal

claude mcp add second-brain -- npx -y @travisbergen2/second-brain-mcp --vault

This one needs values on its command line, so copy the settings and fill them in.

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "second-brain": {
      "command": "npx",
      "args": [
        "-y",
        "@travisbergen2/second-brain-mcp",
        "--vault"
      ]
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

This one needs values on its command line, so copy the settings and fill them in.

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "second-brain": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@travisbergen2/second-brain-mcp",
        "--vault"
      ]
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

This one runs on your computer, and ChatGPT can only connect to servers on the internet. Pick another app.

Your choice stays on this device in a cookie; no account needed.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

Runs on your computer; the tool list appears in your AI app after you install it.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 7, 2026

  • ✓ Pass

    Maker matches the repo

    The registry name was verified with the GitHub account travisbergen2, which owns the repo

  • … Not checked yet

    Still maintained

    We have not read this repo from GitHub yet

  • … Not checked yet

    Has a licence

    We have not read this repo from GitHub yet

  • – Not applicable

    Endpoint responds

    This one runs on your computer; there is no internet endpoint

  • – Not applicable

    Sign-in with OAuth

    Runs on your computer and uses local settings instead

  • … Not checked yet

    No hidden instructions in tool descriptions

    Runs on your computer; we can only read tool lists from internet endpoints

Compared with others in Docs, sheets & office worki

  • More stars than 0% of the other 2186 servers in this category
  • Published to the registry more recently than 30% of the other 2186 servers in this category
  • Basic checks equal to or better than 100% of the other 2186 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is Explicit Formula — Second Brain safe?

It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

The registry does not list a required key, though some servers ask you to sign in on first use.

Does it run on my computer or in the cloud?

It runs on your computer. Your AI app starts it when needed, and data does not pass through the maker’s servers (unless it calls an online service itself).

Is it still maintained?

The GitHub repo last changed –, and the latest version (0.1.0) reached the registry 2 months ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. You also need Node.js on your computer.

What can I use instead?

In the same category: Agent-Native Calendar, Excel MCP Server, MCP Server for Excel

Alternatives

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Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

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Runs in the cloud★ 7,620MITUpdated 2 months ago
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Excel MCP Server

by haris-musa

Lets AI create and edit Excel files itself, including formulas, charts and PivotTables, without Excel installed.

Runs on your computer★ 4,276MITUpdated 6 days ago
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Excel automation for AI - Sheets, Power Query, DAX, VBA, Tables, Ranges and more. Windows only.

Runs on your computer★ 847MITUpdated 3 days ago
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README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

RPCS-1 SDK — AI Agent Tuner

Start with the free tuner: find your AI agent’s likely failure mode, get runtime settings to try, and validate them with a harder case.

RPCS-1 helps teams make agent settings deliberate rather than guessed. Describe the task, change rate, predictability, stakes, relevant context horizon, and commitment style; it returns a five-primitive profile, a runtime recommendation, and a next test. The suite also includes SendRight for catching ambiguous prompts before handoff and the Translation Bridge for profile-aware communication rendering.

Repository Structure

rpcs1-sdk/

├── packages/core/ # TypeScript engine (@rpcs1/core): tuner + translation layer + receiver-profile intake ├── packages/web/ # Next.js app serving rpcs1.dev (tuner, translator, docs, Stripe, /mcp endpoint) ├── packages/mcp-server/ # Standalone STDIO MCP server (what Glama and MCP clients build) ├── sdk/python/ # Python SDK (pip install rpcs1) ├── skills/ # Canonical agent skill package (HF-HATP v2.0 SKILL.md) ├── docs/ # Architecture, deployment, launch playbook └── .github/workflows/ # CI/CD

Quick Start — Python SDK

pip install rpcs1
from rpcs1 import recommend_params

config = recommend_params( task_description="Customer support agent", environment_entropy="dynamic", environment_predictability="somewhat_predictable", stakes="high", target_platform="anthropic", )

print(config.platform_parameters.temperature) # e.g. 0.52 print(config.predicted_regime) # 'stable' print(config.reasoning) # cites Matching Principle

Quick Start — TypeScript Core

import { recommend } from '@rpcs1/core';

const rec = recommend({ task: { task_summary: 'Customer support agent' }, environment: { entropy: 'dynamic', predictability: 'somewhat_predictable', stakes: 'high', context_relevance: 'medium', commitment_style: 'cautious', }, target_platform: 'anthropic', });

console.log(rec.platform_parameters.temperature); console.log(rec.predicted_regime);

Development

# Install dependencies

npm ci --include=optional

Build and test TypeScript core

npm run build --workspace=@rpcs1/core npm run test --workspace=@rpcs1/core

Test Python SDK

cd sdk/python pip install -e ".[dev]" pytest -v

Web environment variables are documented in packages/web/.env.example (Stripe, Resend, license signing, rate limits). MCP production controls are listed under Production controls below.

The web app deploys to Vercel on Node 24 (region iad1); pushes to main trigger the production deployment.

The Matching Principle

The SDK implements Pred-09-5 from IMM Paper 9:

Stable receivers in an environment with entropy H satisfy TI ~ 1/H.

High-entropy environments → short attention windows (TI ~ 10). Low-entropy environments → long attention windows (TI ~ 90).

Every parameter recommendation traces back to this principle or the basin stability geometry (oscillation/overload/freeze boundary conditions).

Web App

The site can also explain the same product facts in technical, executive, plain-language, or literal-and-precise registers. The explanation changes; pricing, deliverables, and limitations do not.

Brand — Explicit Formula (product) / RPCS-1 (mechanism)

The site fronts one consumer product: Explicit Formula — the box on the landing page. *Explicit*: says exactly what it means (the product's one job); *formula*: a repeatable method. The wordmark is an advisory-sticker homage (components/StickerLogo.tsx), deliberately distinct from the trademarked RIAA label.

The mechanism brand — RPCS-1, the receiver engine, its laws, and its scorecard — is unchanged and renders as "Powered by RPCS-1" in the footer. House rule: outcome on the wrapper, mechanism one click deep.

  • The brand is a token: packages/web/lib/brand.ts. Renaming the product is one env var (NEXT_PUBLIC_BRAND_NAME) or one line — no other code changes.
  • Every station that used to compete for the nav (SendRight, Bridge, Translator, Calibrate, Tuner, R&D, …) stays live at its original route and is indexed at /labs (packages/web/lib/labs.ts).
  • The consumer domain follows the deployment: set NEXT_PUBLIC_APP_URL when it goes live. rpcs1.dev remains the mechanism home either way.

SendRight (Interpretation Mirror + Hand-off)

SendRight is the type-and-send front door: type a prompt the way you'd say it out loud, see the readings it actually supports, lock in the one you meant, and hand it to your own model app with one click.

Modules (packages/core):

  • mirror(text) — deterministic fork detectors (no ML, no API calls). Returns { clean, readings[], ambiguousSpans[] }. Detectors: compare-or-choose ("X or Y?" questions without an explicit verb), grouping forks ("A and B or C"), scope forks ("only ... and ..."), dangling pronouns, bare objects ("fix it"), external references ("the above"). Contract: silent on clean prompts — zero-fork controls in tests/mirror.test.ts enforce it. Pure function, callable from any front end (web box, NL2Build, CLI).
  • applyReading(text, clarifier) — appends the chosen reading's clarifier so the locked interpretation travels with the prompt.
  • buildHandoff(vendor, prompt) / listVendors() — per-vendor capability table for opening the user's own model app with the prompt pre-filled. Prefill URL parameters are undocumented vendor behavior and churn without notice; each entry carries a verified date and must be re-checked at release. Verified 2026-07-25: ChatGPT, Claude, Perplexity, Grok support URL prefill; Gemini and Copilot are clipboard-fallback only. Logged-out users may lose the prefill at login. All vendors degrade gracefully to clipboard.

Web: /send (packages/web/app/send) renders the box via components/SendBox.tsx — mirror runs client-side (debounced, zero network); the hand-off happens in the user's own app. SendRight never makes the model call and never sees the answer.

Feasibility boundary (honest scope): reasoning-stream digests and mid-generation stop/realign are only possible where rpcs1 itself owns the API call (the fan-out / power-user mode, not yet shipped). They are structurally impossible in vendor chat UIs and via the MCP surface — SendRight's hand-off path intentionally trades those away for zero keys, zero cost, and zero data custody.

MCP Server

RPCS-1 is also available as a public, anonymous, read-only MCP server:

https://rpcs1.dev/mcp

It exposes eight read-only tools across four families:

  • recommend_agent_configuration — diagnose an AI agent against environmental entropy, predictability, stakes, context horizon, and commitment style; receive runtime settings to try and a next test.
  • interpret, normalize, and rewrite — detect ambiguity, turn fragmented text into coherent prose, and return style-specific rewrite instructions.
  • route_intent — entropy routing over competing interpretations of a message: the calling model proposes candidate readings (paraphrases and priors); the deterministic router computes the posterior and decides commit, present options, or clarify. The commit-vs-clarify authority in the pipeline.
  • calibrate_profile, prepare_prompt, and render_reply — create a continuous communication-preference profile, recover intended meaning before an action, and render a reply for that profile.
Translation Layer

"Say what you mean. Hear what they meant."

The Translation Bridge treats the profile as a transportable parameter, not a category label. The five-question Calibrate flow measures communication preferences for rendering only; it is not a psychological assessment or diagnosis. prepare_prompt / render_reply use that profile on the inbound and outbound sides of an interaction. The canonical agent-facing specification lives at skills/rpcs1-translation-layer/SKILL.md.

Tuner examples

The first useful call is a support copilot under live pressure:

Use recommend_agent_configuration to diagnose my support copilot.

Task: refund and billing dispute triage Environment: dynamic, somewhat_predictable, high stakes Context relevance: medium Commitment style: cautious Target platform: anthropic

The output should lead with the five-primitive profile, failure-risk score, predicted regime, runtime posture, and next test to run.

The second useful call is a coding agent in a changing repository:

Use recommend_agent_configuration to diagnose my coding agent.

Task: inspect a changing repository, edit files, run tests, and open a pull request Environment: moderate, somewhat_predictable, medium stakes Context relevance: long Commitment style: balanced Target platform: openai

The output should still lead with the five-primitive profile, failure-risk score, predicted regime, runtime posture, and next test to run.

Connection details and client compatibility notes are available at https://rpcs1.dev/docs/mcp. Practical coding, support, and research examples are available at https://rpcs1.dev/docs/examples.

Hyperagent uses the fixed public OAuth client hyperagent-rpcs1 with PKCE and the registered callback https://hyperagent.com/api/mcp-servers/callback. No client secret is required.

The MCP surface exposes the deterministic agent-tuning workflow alongside read-only translation and per-user rendering tools. New tools should be added only after their scoring or behavior contracts are implemented and tested in the core package.

Discovery metadata:

Production controls:

  • MCP_HOURLY_LIMIT controls per-instance MCP throttling (default: 120 requests per IP/hour).
  • MCP_MAX_BODY_BYTES limits request bodies (default: 65536 bytes).
  • MCP_ALLOWED_HOSTS is a comma-separated production host allowlist.
  • MCP_ALLOWED_ORIGINS is an optional comma-separated browser-origin allowlist. Leave it blank to reject cross-origin browser requests.
  • MCP_OAUTH_JWT_SECRET signs short-lived OAuth authorization codes and access tokens.
  • /api/health reports deployment and MCP readiness metadata.

For globally consistent abuse protection across Vercel instances, configure a Vercel Firewall rate-limit rule for /mcp. The in-process limiter is defense in depth, not a distributed quota.

Glama Docker checks should build and launch the local STDIO server, not connect to the hosted https://rpcs1.dev/mcp endpoint. Use this build spec:

{

"buildSteps": [ "npm ci --include=optional", "npm run build --workspace=@rpcs1/core", "npm run build --workspace=@rpcs1/mcp-server" ], "cmdArguments": [ "mcp-proxy", "--", "node", "packages/mcp-server/dist/index.js" ], "environmentVariablesJsonSchema": { "type": "object", "properties": {}, "required": [] }, "placeholderArguments": {} }

Only the beginning is shown; read the rest in the repo

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