api-gateway

api-gateway is a skill for Claude Code, Codex from G1Joshi/Agent-Skills. It costs 16 tokens per session (462 once invoked), scanned A, original, MIT.

A service placed between apps such as websites or mobile clients and the backend services they call. It routes requests and can combine several service responses into one.

In plain words
What is it for?
Use it as the front door for microservices, to route requests, combine data for a screen, or apply shared request rules.
Why use it?
It hides the complexity of a multi-service backend from clients. It also gives one place for authentication, rate limits, logging, caching, and protocol conversion.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

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 skills/g1joshi/agent-skills/api-gateway
Any agent
npx skills add G1Joshi/Agent-Skills --skill api-gateway
Clone the repo
git clone --depth 1 https://github.com/G1Joshi/Agent-Skills

Made for: Claude Code, Codex.

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 api-gateway

README.md
[![agentmods](https://agentmods.dev/badge/skills/g1joshi/agent-skills/api-gateway.svg)](https://agentmods.dev/skills/g1joshi/agent-skills/api-gateway)
Your own site
<a href="https://agentmods.dev/skills/g1joshi/agent-skills/api-gateway"><img src="https://agentmods.dev/badge/skills/g1joshi/agent-skills/api-gateway.svg" alt="Measured on agentmods" height="20"></a>
Per session 16 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 462 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 $0.00016 $0.00462
Opus 5 $0.00008 $0.00231
Sonnet 5 $0.00003 $0.00092
Haiku 4.5 $0.00002 $0.00046

Measured 6d ago against content hash e4bb37e073ce, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

api-gateway 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.

skills/architecture/api-gateway/SKILL.md · 62 lines

How it starts

The opening of the file, as written. The whole thing — 62 lines — stays where its author put it; the contents beside it link to each section on GitHub.

API Gateway

An API Gateway sits between clients (Mobile, Web) and services. It acts as a reverse proxy, accepting all API calls, aggregating the various services required to fulfill them, and returning the appropriate result.

When to Use

  • Microservices: Essential to hide the complexity of backend services (Service Discovery).
  • Cross-Cutting Concerns: Centralizing Authentication, SSL Termination, Rate Limiting, and Logging.
  • Protocol Translation: Converting HTTP (Client) to gRPC (Internal).

Core Functionality

Routing

GET /users -> User Service GET /orders -> Order Service

Aggregation (BFF - Backend for Frontend)

Combining results. One request to Gateway -> Calls User Service + Order Service -> Returns combined JSON.

Offloading

  • Auth: Validating JWT tokens at the edge.
  • Cache: Serving static or cached responses.

Common Patterns

Backend for Frontend (BFF)

Creating specific gateways for different clients (e.g., one for Mobile with small payloads, one for Web with rich payloads).

Best Practices

Do:

  • Use mature tools: Kong, Traefik, AWS API Gateway, Nginx.
  • Implement Rate Limiting to prevent DoS.
  • Use Correlation IDs for tracing requests across services.

Don't:

  • Don't put business logic in the Gateway (It's not a service).
  • Don't let it become a Single Point of Failure (High Availability is key).

Troubleshooting

Error Cause Solution
502 Bad Gateway Upstream service down or unreachable. Check internal service health and firewall rules.
504 Gateway Timeout Upstream taking too long. Optimize service or increase timeout (carefully).

References

Read the full file on GitHub · 62 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 · 62 lines · 16 tokens per session scan A e4bb37e073ce

Subscribe to this mod's changes

api-gateway is a skill published in the GitHub repository G1Joshi/Agent-Skills (12 stars, last pushed 6mo ago), licensed MIT. It adds 16 tokens to every session and 462 once invoked, about $0.0001 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 2026-08-30.

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