Jarvis: Skill for Claude Code

.claude/skills/senior-architect/SKILL.md

senior-architect is a skill for Claude Code from Szesnasty/Jarvis. It costs 48 tokens per session (647 once invoked), scanned A, original, Apache-2.0.

A guide for planning and assessing how software systems are structured, including web apps, APIs, databases, and distributed systems.

In plain words
What is it for?
Use it to design a new system, assess an existing one, compare technical options, plan a migration, or record important decisions in Architecture Decision Records (short documents explaining why a choice was made).
Why use it?
It helps turn vague technical choices into decisions based on scale, team, budget, integrations, and required features. It also makes migrations more manageable by breaking them into backward-compatible steps.

Skill for Claude Code

Written for Claude Code: installed under .claude/.

This is Szesnasty/Jarvis's own configuration. It tells Claude Code how to work on Jarvis itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything Jarvis configures →

Reuse

Borrowing it

Nothing to install: this file belongs to Szesnasty/Jarvis. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/Szesnasty/Jarvis/main/.claude/skills/senior-architect/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/Szesnasty/Jarvis

Made for: Claude Code.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for senior-architect

README.md
[![agentmods](https://agentmods.dev/badge/skills/szesnasty/jarvis/senior-architect/github.svg)](https://agentmods.dev/skills/szesnasty/jarvis/senior-architect)
Your own site
<a href="https://agentmods.dev/skills/szesnasty/jarvis/senior-architect"><img src="https://agentmods.dev/badge/skills/szesnasty/jarvis/senior-architect/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for senior-architect

Your own site · 80×15
<a href="https://agentmods.dev/skills/szesnasty/jarvis/senior-architect"><img src="https://agentmods.dev/badge/skills/szesnasty/jarvis/senior-architect.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 48 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 647 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00048 $0.00647
Opus 5 $0.00024 $0.00324
Sonnet 5 $0.00010 $0.00129
Haiku 4.5 $0.00005 $0.00065

Measured 11d ago against content hash fdee4bad838f, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

senior-architect scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 11d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/skills/senior-architect/SKILL.md · 92 lines

How it starts

The opening of the file, as written. The whole thing — 92 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Software Architecture

When making architectural decisions, follow this process:

1. Understand Constraints First

Before proposing any solution:

  • What are the scale requirements? (users, data volume, request rate)
  • What's the team size and skill set?
  • What's the timeline and budget?
  • What existing systems must this integrate with?
  • What are the non-negotiable requirements vs nice-to-haves?

2. Architecture Decision Process

For New Systems

  1. Identify the core domain entities and their relationships
  2. Define the system boundaries and integration points
  3. Choose patterns based on actual requirements, not trends
  4. Document decisions as ADRs (Architecture Decision Records)

For Existing Systems

  1. Map the current architecture — what exists, what's painful
  2. Identify the specific problems to solve (don't boil the ocean)
  3. Propose incremental changes with clear migration paths
  4. Ensure backward compatibility during transition

3. Patterns to Consider

Choose based on the problem, not the hype:

Problem Consider Avoid If
Simple CRUD app Monolith + REST You have <5 developers
Independent scaling needs Microservices Team is small or inexperienced
Complex business rules Domain-Driven Design Domain is simple
Real-time data Event-driven / CQRS Consistency is critical
High read/write ratio Read replicas / caching Data must be real-time

4. Evaluate Trade-offs

Every architectural decision is a trade-off. Make them explicit:

  • Consistency vs Availability — which matters more for this use case?
  • Simplicity vs Flexibility — will we actually need the flexibility?
  • Performance vs Maintainability — where's the real bottleneck?
  • Build vs Buy — is this a core differentiator or commodity?

5. Output Format

For architecture proposals, use:

## Architecture: [system/component name]

### Context
What problem are we solving and why now?

### Decision Drivers
- [constraint or requirement]

### Proposed Architecture
[description with diagram if multiple components]

### Trade-offs
| Choice | Benefit | Cost |
|--------|---------|------|

### Alternatives Considered
[what else was evaluated and why it was rejected]

### Migration Path
[how to get from here to there incrementally]

Read the full file on GitHub · 92 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 11d ago First seen · 92 lines · 48 tokens per session scan A fdee4bad838f

Subscribe to this mod's changes

senior-architect is a skill published in the GitHub repository Szesnasty/Jarvis (10 stars, last pushed 3mo ago), licensed Apache-2.0. It adds 48 tokens to every session and 647 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

Other skills, from other repositories

shodh-memory

Persistent memory system for AI agents. Use this skill to remember context across conversations, recall relevant information, and build long-term knowledge. Activate when you need to store decisions, learnings, errors, or context that should persist beyond the current session.

varun29ankuS/shodh-memory · 53 tokens

binder-app

Build a small HTTP app (dashboard, kanban board, admin panel, custom UI) on top of an existing Binder workspace. Use when asked to "create an app", "build a dashboard", "show records in a chart", "make a kanban/board", "build an admin panel", or "add a UI on top of binder".

mpazik/Binder · 74 tokens

algolia-cli

Use this skill whenever a user wants to execute operations against Algolia indices or accounts — deleting records, copying/migrating indices, backing up data, importing/exporting records, managing API keys, editing synonyms, configuring rules, changing settings like facets, clearing indices, or automating Algolia in…

algolia/skills · 166 tokens

algolia-discovery-planning

START HERE for any non-trivial Algolia work — building, adding, migrating, redesigning, auditing, or configuring search, browse, autocomplete, indexing, relevance, recommendations, personalization, merchandising, events, or analytics. Invoke this FIRST even when the task already seems scoped or the user names one…

algolia/skills · 222 tokens

algolia-migration

Migrate existing Algolia API client code to a newer major version. Triggers on: upgrading algoliasearch, moving from initIndex to client methods, fixing "initIndex is not a function", updating imports after a version bump, handling breaking changes from v3→v4 or v4→v5, replacing .wait() chaining, or any mention of…

algolia/skills · 183 tokens

algolia-quickstart

Use this skill to set up and provision Algolia from scratch: create a new Algolia account, sign up, log in / authenticate the Algolia CLI, or provision a new application to obtain an App ID and API key. Trigger when a user is getting started with Algolia and has no account, no application, or no credentials yet — e.g.…

algolia/skills · 162 tokens