Borrowing it
Nothing to install: this file belongs to nirholas/XActions. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/nirholas/XActions/main/xspace-agents/.github/instructions/core-sdk.instructions.mdgit clone --depth 1 https://github.com/nirholas/XActionsWrote 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/instructions/nirholas/xactions/core-sdk)<a href="https://agentmods.dev/instructions/nirholas/xactions/core-sdk"><img src="https://agentmods.dev/badge/instructions/nirholas/xactions/core-sdk.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00592 | $0.00592 |
| Opus 5 | $0.00296 | $0.00296 |
| Sonnet 5 | $0.00118 | $0.00118 |
| Haiku 4.5 | $0.00059 | $0.00059 |
Grade A, and why
XActions core-sdk.instructions.md 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 3d 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 — 45 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Core SDK (packages/core/)
Published as xspace-agent on npm. See packages/core/CLAUDE.md for the full module map.
Key Classes
| Class | File | Purpose |
|---|---|---|
XSpaceAgent |
src/agent.ts |
Main entry point, orchestrates all subsystems |
AgentTeam |
src/team.ts |
Multi-agent coordination on shared browser |
BrowserLifecycle |
src/browser/lifecycle.ts |
Puppeteer launch → login → join → leave → stop |
AudioPipeline |
src/audio/pipeline.ts |
Capture → VAD → silence → encode chain |
StateMachine |
src/fsm/machine.ts |
Generic FSM engine for agent/team lifecycle |
SelectorEngine |
src/browser/selector-engine.ts |
Self-healing CSS/text/aria selector strategies |
ProviderRouter |
src/providers/router.ts |
Multi-provider LLM routing |
Patterns
- Provider interfaces:
LLMProvider,STTProvider,TTSProviderinsrc/types.ts— must implementstreamResponse()/transcribe()/synthesize(),checkHealth(),getMetrics(),estimateCost() - Provider factories:
createLLM(),createSTT(),createTTS()insrc/pipeline/ - Error classes: All extend
XSpaceErrorinsrc/errors.tswithcode,message,hint,docsUrl - FSM transitions:
idle→launching→authenticating→joining→listening→speaking→leaving→stopped - Middleware hooks:
before:stt → after:stt → before:llm → after:llm → before:tts → after:tts - Config validation: Zod schemas in
src/config.ts
Rules
- Never hardcode X Space CSS selectors — add alternatives to
SelectorEngine - Never bypass the FSM for agent state transitions — use
StateMachine - All new errors must extend
XSpaceErrorwith a code and hint - New providers must implement the full interface including health/metrics/cost
- No database dependencies — persistence is file-based (JSON + gzip)
Commands
cd packages/core && pnpm test # vitest run
cd packages/core && pnpm build # tsc → dist/
cd packages/core && pnpm test:coverage # vitest with coverage
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.
- 3d ago First seen · 45 lines · 592 tokens per session scan A 6c1a8fbc8ffe
XActions core-sdk.instructions.md is an instructions file published in the GitHub repository nirholas/XActions (512 stars, last pushed today), licensed Apache-2.0. It adds 592 tokens to every session, about $0.0030 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 2026-09-03.
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