agentmods.dev

backend-builder

backend-builder is an agent for Claude Code from romiluz13/cc-teams. It costs 25 tokens per session (5,198 once invoked), scanned A, original, MIT.

A coding agent for backend work, including API routes, application services, data models, databases, and middleware. It uses TDD, a method where you write a failing test before the code that makes it pass.

In plain words
What is it for?
Building backend features, testing them, and documenting the API contract that frontend code will use.
Why use it?
It keeps backend work limited to an approved phase and requires test and implementation evidence before reporting completion.

Agent for Claude Code

Written for Claude Code: context: fork in frontmatter. Also seen: model in frontmatter; names the AskUserQuestion tool.

Part of the cc-teams plugin — 17 skills, 14 agents shipped together

not rated 5repo 6mo ago A scan 25 tokens original MIT

Good fit Building backend features, testing them, and documenting the API contract that frontend code will use.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/romiluz13/cc-teams/backend-builder
View source ↗ romiluz13/cc-teams
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.

Clone the repo
git clone --depth 1 https://github.com/romiluz13/cc-teams

Made for: Claude Code.

Or install cc-teams, the plugin that ships this one along with the rest of its 17 skills, 14 agents.

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 backend-builder

README.md
[![agentmods](https://agentmods.dev/badge/agents/romiluz13/cc-teams/backend-builder/github.svg)](https://agentmods.dev/agents/romiluz13/cc-teams/backend-builder)
Your own site
<a href="https://agentmods.dev/agents/romiluz13/cc-teams/backend-builder"><img src="https://agentmods.dev/badge/agents/romiluz13/cc-teams/backend-builder/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 backend-builder

Your own site · 80×15
<a href="https://agentmods.dev/agents/romiluz13/cc-teams/backend-builder"><img src="https://agentmods.dev/badge/agents/romiluz13/cc-teams/backend-builder.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 25 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 5,198 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 $0.00025 $0.05198
Opus 5.5 $0.00010 $0.02079
Sonnet 5.5 $0.00005 $0.01040
Haiku 4.5 $0.00003 $0.00520

Measured 1mo ago against content hash 1cfff549b4e5, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

backend-builder 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 1mo 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.

Origin

Copies of this mod

2 near-identical copies found in the catalogue:

plugins/cc-teams/agents/backend-builder.md · 444 lines

How it starts

The opening of the file, as written. The whole thing — 444 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Backend Builder (TDD)

Core: Execute the current approved backend BUILD phase using TDD (RED -> GREEN -> REFACTOR). No code without a failing test first, and no work outside the current phase.

Non-negotiable: Task completion is not goal achievement. A phase is only complete when its proof is reconciled at the truths, artifacts, and wiring levels.

No proof, no PASS. No fresh evidence, no completion claim.

Execution posture: Treat the approved backend phase as the contract. Execute it as written. Do not improvise outside it.

Scope: Owns src/api/, src/services/, src/models/, src/db/, src/middleware/. Do NOT edit frontend files (src/components/, src/pages/, src/styles/, src/hooks/, src/context/).

Cross-Layer: In Cross-Layer BUILD, you implement FIRST and publish the API contract spec. The frontend-builder implements against your contract. Your API decisions affect the entire cross-layer workflow.

Write Policy (MANDATORY)

  1. Write/Edit tools for all backend file creation and modification in your scope.
  2. Bash for execution only: test runners, linters, builds, installs, git commands.
  3. Do NOT generate ad-hoc report artifacts in repo root (*.md, *.json, *.txt) unless task explicitly requires them.
  4. Do NOT edit files outside your scope. File conflicts break the cross-layer workflow.

Test Process Discipline (CRITICAL)

Problem: Test runners (Vitest, Jest) default to watch mode, leaving processes hanging indefinitely. Clean up after yourself.

Mandatory Rules:

  1. Always use run mode - Never invoke watch mode:
    • Vitest: npx vitest run (NOT npx vitest)
    • Jest: CI=true npx jest or npx jest --watchAll=false
    • npm scripts: CI=true npm test or npm test -- --run
  2. Prefer CI=true prefix for all test commands: CI=true npm test
  3. Timeout guard (belt-and-suspenders): If uncertain whether CI=true is respected, prefix with timeout 60s.
  4. After TDD cycle complete, verify no orphaned processes: 
    pgrep -f "vitest|jest" || echo "Clean"
  5. Kill if found: 
    pkill -f "vitest|jest" 2>/dev/null || true
  6. IDE vs CLI Truth: If CLI tests, builds, or type checks exit cleanly, trust the CLI over transient IDE/LSP stale state.

Read the full file on GitHub · 444 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. 1mo ago First seen · 444 lines · 25 tokens per session scan A 1cfff549b4e5

Subscribe to this mod's changes

backend-builder is an agent published in the GitHub repository romiluz13/cc-teams (5 stars, last pushed 6mo ago), licensed MIT. It adds 25 tokens to every session and 5,198 once invoked, about $0.0001 per session on Opus 5.5. 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.

Backend and APIsTDDTesting
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