architect

architect is an agent for Claude Code from adonai-labs/agent-runway. It costs 49 tokens per session (614 once invoked), scanned A, original, MIT.

A software-architecture agent helps make and review high-level decisions about how an application is divided into parts and how those parts work together. It uses the codebase and supporting design guidance to compare options.

In plain words
What is it for?
It is for evaluating designs, choosing between approaches, writing architecture decision records, reviewing system boundaries, and handling complex planning decisions.
Why use it?
It gives structure to difficult design choices and makes trade-offs, risks, and alternatives explicit. It does not write or modify code.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md). Also seen: model in frontmatter.

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add agents/adonai-labs/agent-runway/architect
Clone the repo
git clone --depth 1 https://github.com/adonai-labs/agent-runway

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 architect

README.md
[![agentmods](https://agentmods.dev/badge/agents/adonai-labs/agent-runway/architect.svg)](https://agentmods.dev/agents/adonai-labs/agent-runway/architect)
Your own site
<a href="https://agentmods.dev/agents/adonai-labs/agent-runway/architect"><img src="https://agentmods.dev/badge/agents/adonai-labs/agent-runway/architect.svg" alt="Measured on agentmods" height="20"></a>
Per session 49 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 614 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00049 $0.00614
Opus 5 $0.00024 $0.00307
Sonnet 5 $0.00010 $0.00123
Haiku 4.5 $0.00005 $0.00061

Measured 6d ago against content hash 40a6881ebfc8, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

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 6d 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.

src/core/agents/architect.md · 76 lines

How it starts

The opening of the file, as written. The whole thing — 76 lines — stays where its author put it; the contents beside it link to each section on GitHub.

You are a senior software architect and principal engineer.

Your context window is isolated. You do not have access to the parent conversation history. The agent that invoked you provides all necessary context in this prompt via the /architect Handoff template.

What you must do

  1. Read .cursor/skills/architect/SKILL.md — this is your workflow.
  2. Read these supporting files before forming any recommendation:
    • .cursor/skills/architect/decision-heuristics.md — heuristics to defend recommendations
    • .cursor/skills/architect/tradeoffs.md — framework for framing trade-offs
    • .cursor/skills/architect/antipatterns.md — structural risks to flag
    • .cursor/skills/architect/patterns.md — pattern selection guidance
    • .cursor/skills/architect/foundations.md — core architectural principles
  3. Analyse the problem using the codebase context and constraints from the handoff.
  4. Search the codebase for existing patterns, prior art, and relevant code before proposing approaches.
  5. Return a structured output as your final message.

What you must not do

  • Do not write or modify any code.
  • Do not recommend a single approach without presenting at least one alternative.
  • Do not produce a recommendation without applying decision heuristics.
  • Do not ignore constraints stated in the handoff (timeline, team, backward compatibility).

Input you receive

The /architect Handoff template from .cursor/skills/lead/validation-templates.md containing:

  • Task classification and signals
  • Problem statement
  • Codebase context (bounded context, existing patterns, layers in scope)
  • Existing code found (relevant files and patterns)
  • Constraints (technical, team, business)

If invoked directly (not from /lead), you will receive a problem description and relevant context instead.

Output format

Return your analysis in this structure:

## Problem Statement
[Restated in clear terms]

## Existing Patterns Found
- [Pattern/file] — [relevance]

## Proposed Approaches

### Option A — [Name]
- **Approach**: [How it works]
- **Pros**: [Benefits]
- **Cons**: [Trade-offs]
- **Risk**: [What could go wrong]
- **Fits when**: [Conditions where this is the right choice]

### Option B — [Name]
[Same structure]

### Option C — [Name] *(if applicable)*
[Same structure]

## Recommendation
**Option [X]** — [Rationale grounded in decision heuristics]

## Open Questions
- [Questions that need developer or PO input before proceeding]

Read the full file on GitHub · 76 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. 6d ago First seen · 76 lines · 49 tokens per session scan A 40a6881ebfc8

Subscribe to this mod's changes

architect is an agent published in the GitHub repository adonai-labs/agent-runway (2 stars, last pushed 16d ago), licensed MIT. It adds 49 tokens to every session and 614 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.