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 ericrisco/rsc-harness --skill api-connector-buildergit clone --depth 1 https://github.com/ericrisco/rsc-harnessWrote 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/ericrisco/rsc-harness/api-connector-builder)<a href="https://agentmods.dev/skills/ericrisco/rsc-harness/api-connector-builder"><img src="https://agentmods.dev/badge/skills/ericrisco/rsc-harness/api-connector-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.
<a href="https://agentmods.dev/skills/ericrisco/rsc-harness/api-connector-builder"><img src="https://agentmods.dev/badge/skills/ericrisco/rsc-harness/api-connector-builder.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 4 findings, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Privilege Escalation · line 51 Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
- high Privilege Escalation · line 58 Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.Fix: Remove references to credential paths. Use environment variables or secrets managers. For docs, use placeholder paths (e.g., /path/to/config). Never load .env or token files in production code paths.
- medium Data Exfiltration · line 222 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
- medium Data Exfiltration · line 232 Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
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 | $0.00080 | $0.03443 |
| Opus 5.5 | $0.00032 | $0.01377 |
| Sonnet 5.5 | $0.00016 | $0.00689 |
| Haiku 4.5 | $0.00008 | $0.00344 |
Grade A, and why
api-connector-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.
How it starts
The opening of the file, as written. The whole thing — 269 lines — stays where its author put it; the contents beside it link to each section on GitHub.
API connector builder — auth, pagination, retries, rate limits
You are writing a client for someone else's HTTP API. You do not own the contract; you obey it. The deliverable is one typed connector module per vendor that authenticates, walks the whole result set, retries only transient failures with backoff, and stays under the rate limit without getting the key banned. One connector = one vendor: mixed clients tangle two auth schemes and two rate-limit budgets into something no one can reason about.
Four pillars, every time: auth, pagination, retries, rate limits. If your connector skips any one of them it works in the demo and breaks in production — on page 2, on token expiry, on the first 429, or on a flaky network.
Step 0 — read the contract
Read the vendor docs before writing a line — invented endpoints and guessed field names 404 in prod. Extract these first; each one changes what you write, so missing one means a rewrite.
| Find in their docs | Why it changes your code |
|---|---|
| Auth scheme + token TTL | Picks the flow below; TTL decides if you need refresh |
| Base URL and version | Wrong version = silent 404s or deprecated field shapes |
| Rate-limit header names | You cannot throttle to a budget you cannot read |
| Pagination style | Cursor vs offset vs Link vs Relay = different loop |
| Error envelope shape | Where the real error code lives (body, not always status) |
| Idempotency support | Decides whether POST is safe to retry (key header?) |
If a fact is not in the docs, probe one real call and read the response headers and body — do not assume.
Auth — pick the flow, then store the secret right
OAuth 2.1 is the current baseline. Three deltas you must honor: PKCE is mandatory for every authorization-code client, the Implicit and Resource-Owner-Password grants are removed, and bearer tokens may not travel in query strings (header only) — query strings end up in logs and referrers. (oauth.net/2.1, accessed 2026-06-02.)
What ships with it
5 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.
- 1mo ago First seen · 269 lines · 80 tokens per session scan A dd35fdbbe462
api-connector-builder is a skill published in the GitHub repository ericrisco/rsc-harness (232 stars, last pushed today), licensed MIT. It adds 80 tokens to every session and 3,443 once invoked, about $0.0003 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 2026-08-30.
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