React is a JavaScript library for building user interfaces from reusable components whose output changes as application data changes. It is used by web and mobile developers to create interactive interfaces, including server-rendered web experiences and React Native apps.
Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/react/reactnpx agentmods add skills/react/react/compiler-orchestratorWrote 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/react/react/compiler-orchestrator)<a href="https://agentmods.dev/skills/react/react/compiler-orchestrator"><img src="https://agentmods.dev/badge/skills/react/react/compiler-orchestrator/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/react/react/compiler-orchestrator"><img src="https://agentmods.dev/badge/skills/react/react/compiler-orchestrator.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Snyk pass
- 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 | $0.00038 | $0.03382 |
| Opus 5.5 | $0.00015 | $0.01353 |
| Sonnet 5.5 | $0.00008 | $0.00676 |
| Haiku 4.5 | $0.00004 | $0.00338 |
Grade A, and why
compiler-orchestrator 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 — 274 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Compiler Orchestrator
Automatically drive the Rust compiler port forward by discovering the current state, fixing failures, porting new passes, reviewing, and committing — in a continuous loop.
Arguments:
- $ARGUMENTS: Optional. A pass name to start from, or
statusto just report current state without acting.
Pass Order Reference
These are the passes in Pipeline.ts order, with their exact log names:
| # | Log Name | Kind | Notes |
|---|---|---|---|
| 1 | HIR | hir | |
| 2 | PruneMaybeThrows | hir | Validation: validateContextVariableLValues, validateUseMemo after |
| 3 | DropManualMemoization | hir | Conditional |
| 4 | InlineImmediatelyInvokedFunctionExpressions | hir | |
| 5 | MergeConsecutiveBlocks | hir | |
| 6 | SSA | hir | |
| 7 | EliminateRedundantPhi | hir | |
| 8 | ConstantPropagation | hir | |
| 9 | InferTypes | hir | Validation: validateHooksUsage, validateNoCapitalizedCalls after (conditional) |
| 10 | OptimizePropsMethodCalls | hir | |
| 11 | AnalyseFunctions | hir | |
| 12 | InferMutationAliasingEffects | hir | |
| 13 | OptimizeForSSR | hir | Conditional: outputMode === 'ssr' |
| 14 | DeadCodeElimination | hir | |
| 15 | PruneMaybeThrows (2nd) | hir | Reuses existing fn, just needs 2nd call + log in pipeline.rs |
| 16 | InferMutationAliasingRanges | hir | Validation block (8 validators) after (conditional) |
| 17 | InferReactivePlaces | hir | Validation: validateExhaustiveDependencies after (conditional) |
| 18 | RewriteInstructionKindsBasedOnReassignment | hir | Validation: validateStaticComponents after (conditional) |
| 19 | InferReactiveScopeVariables | hir | Conditional: enableMemoization |
| 20 | MemoizeFbtAndMacroOperandsInSameScope | hir | |
| -- | outlineJSX | hir | Between #20 and #21, conditional: enableJsxOutlining, no log entry |
| 21 | NameAnonymousFunctions | hir | Conditional |
| 22 | OutlineFunctions | hir | Conditional |
| 23 | AlignMethodCallScopes | hir | |
| 24 | AlignObjectMethodScopes | hir | |
| 25 | PruneUnusedLabelsHIR | hir | |
| 26 | AlignReactiveScopesToBlockScopesHIR | hir | |
| 27 | MergeOverlappingReactiveScopesHIR | hir | |
| 28 | BuildReactiveScopeTerminalsHIR | hir | |
| 29 | FlattenReactiveLoopsHIR | hir | |
| 30 | FlattenScopesWithHooksOrUseHIR | hir | |
| 31 | PropagateScopeDependenciesHIR | hir | |
| 32 | BuildReactiveFunction | reactive | |
| 33 | AssertWellFormedBreakTargets | debug | Validation |
| 34 | PruneUnusedLabels | reactive | |
| 35 | AssertScopeInstructionsWithinScopes | debug | Validation |
| 36 | PruneNonEscapingScopes | reactive | |
| 37 | PruneNonReactiveDependencies | reactive | |
| 38 | PruneUnusedScopes | reactive | |
| 39 | MergeReactiveScopesThatInvalidateTogether | reactive | |
| 40 | PruneAlwaysInvalidatingScopes | reactive | |
| 41 | PropagateEarlyReturns | reactive | |
| 42 | PruneUnusedLValues | reactive | |
| 43 | PromoteUsedTemporaries | reactive | |
| 44 | ExtractScopeDeclarationsFromDestructuring | reactive | |
| 45 | StabilizeBlockIds | reactive | |
| 46 | RenameVariables | reactive | |
| 47 | PruneHoistedContexts | reactive | |
| 48 | ValidatePreservedManualMemoization | debug | Conditional |
| 49 | Codegen | ast |
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 · 274 lines · 38 tokens per session scan A 8f4e69d1d932
compiler-orchestrator is a skill published in the GitHub repository react/react (251,069 stars, last pushed yesterday), licensed MIT. It adds 38 tokens to every session and 3,382 once invoked, about $0.0002 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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