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.
npx skills add oborchers/fractional-cto --skill rate-limiting-and-securitygit clone --depth 1 https://github.com/oborchers/fractional-ctoWrote 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.
[](https://agentmods.dev/skills/oborchers/fractional-cto/rate-limiting-and-security)<a href="https://agentmods.dev/skills/oborchers/fractional-cto/rate-limiting-and-security"><img src="https://agentmods.dev/badge/skills/oborchers/fractional-cto/rate-limiting-and-security/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.
<a href="https://agentmods.dev/skills/oborchers/fractional-cto/rate-limiting-and-security"><img src="https://agentmods.dev/badge/skills/oborchers/fractional-cto/rate-limiting-and-security.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00079 | $0.03466 |
| Opus 5 | $0.00039 | $0.01733 |
| Sonnet 5 | $0.00016 | $0.00693 |
| Haiku 4.5 | $0.00008 | $0.00347 |
Grade A, and why
rate-limiting-and-security 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 12d 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.
How it starts
The opening of the file, as written. The whole thing — 238 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Guard Every Gate, Log Every Attempt
Rate limiting and security are not features you bolt on before launch. They are load-bearing walls. Stripe rate-limits at 100 requests per second per key. GitHub returns X-RateLimit-Remaining on every single response. Cloudflare rejects millions of malicious requests before they reach origin servers. These companies do not treat protection as optional — they treat it as infrastructure. An unprotected API is not "MVP-ready"; it is a liability waiting for its first spike of traffic or its first automated attacker.
The patterns below are drawn from Stripe, GitHub, Twilio, Cloudflare, the OWASP API Security Top 10 (2023 edition), and the IETF RateLimit header fields draft. Where these sources converge, treat the practice as non-negotiable.
Rate Limiting Algorithms
Choose the algorithm that matches your traffic shape. The sliding window counter is the right default for most APIs.
| Algorithm | Burst Handling | Memory | Accuracy | Best For |
|---|---|---|---|---|
| Fixed Window | Poor (2x burst at boundary) | Very low | Approximate | Simple internal APIs |
| Sliding Window Log | None (strict) | High | Exact | Audit-sensitive endpoints |
| Sliding Window Counter | Good | Low | Very good | Most APIs (recommended) |
| Token Bucket | Controlled burst up to capacity | Low | Good | API gateways, cloud APIs |
| Leaky Bucket | None (queued, adds latency) | Moderate | Exact | Traffic smoothing |
Fixed Window divides time into discrete intervals (e.g., one minute) and counts requests per interval. The problem: 100 requests at 0:59 and 100 at 1:01 produce 200 requests in two seconds — double the intended rate. Only use this for non-critical internal services.
Sliding Window Counter is a hybrid that weights the previous window's count against the current window's position. At 15 seconds into a new minute, 75% of the previous window's count plus 100% of the current window's count approximates the true trailing-window count. Two counters per key, no timestamp storage, no boundary burst. This is the algorithm most production APIs use.
What ships with it
2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 12d ago First seen · 238 lines · 79 tokens per session scan A c2f929e2a933
rate-limiting-and-security is a skill published in the GitHub repository oborchers/fractional-cto (30 stars, last pushed 1mo ago), licensed MIT. It adds 79 tokens to every session and 3,466 once invoked, about $0.0004 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.
Other skills, from other repositories
mem0-oss-to-platform
Plan and then execute a migration of a project from the mem0 open-source / self-hosted SDK (the local Memory class) to the mem0 Platform / hosted / managed SDK (the MemoryClient class). Use this whenever a developer wants to move, switch, or migrate their mem0 usage off OSS/self-hosted to the hosted API — e.g.…
agui-dotnet-protobuf
Use the protobuf wire transport (instead of the default Server-Sent Events) for an AG-UI connection with the AG-UI .NET SDK — a compact binary event stream negotiated via the Accept header. USE FOR: making an AGUIChatClient prefer protobuf by wiring an AGUIEventStreamHandler with ProtobufEventStreamFormatter (then…
azure-mgmt-botservice-dotnet
Azure Resource Manager SDK for Bot Service in .NET. Management plane operations for creating and managing Azure Bot resources, channels (Teams, DirectLine, Slack), and connection settings. Triggers: "Bot Service", "BotResource", "Azure Bot", "DirectLine channel", "Teams channel", "bot management .NET", "create bot".
fastapi-router-py
Create FastAPI routers with CRUD operations, authentication dependencies, and proper response models. Use when building REST API endpoints, creating new routes, implementing CRUD operations, or adding authenticated endpoints in FastAPI applications.
aws-sdk-java-v2-core
Provides AWS SDK for Java 2.x client configuration, credential resolution, HTTP client tuning, timeout, retry, and testing patterns. Use when creating or hardening AWS service clients, wiring Spring Boot beans, debugging auth or region issues, or choosing sync vs async SDK usage.
migrate-segw-to-rap
Reverse-engineer a SEGW-built OData V2 service (MPC/DPC/MPCEXT/DPCEXT) into a modern RAP V4 service — tables, CDS views (interface + projection), behavior definitions, draft entities, service definition + binding. Use when asked to "migrate this SEGW service to RAP", "convert OData V2 to V4 RAP", "modernize this…