diff --git a/scientific-bounty-reviewer-capacity-guard/README.md b/scientific-bounty-reviewer-capacity-guard/README.md
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+# Scientific bounty reviewer capacity guard
+
+This module checks whether a scientific bounty has enough qualified, available reviewers before a review panel is assigned.
+
+It focuses on one slice of the bounty workflow: reviewer capacity. It does not handle payouts, arbitration, escrow, IP transfer, or export control.
+
+## What it checks
+
+- enough eligible reviewers
+- required expertise coverage
+- reviewer conflicts
+- overloaded reviewers
+- stale reviewer training
+
+## Run it
+
+```bash
+node scientific-bounty-reviewer-capacity-guard/test.js
+node scientific-bounty-reviewer-capacity-guard/demo.js
+```
+
+The demo writes a JSON result and Markdown report to `artifacts/`.
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diff --git a/scientific-bounty-reviewer-capacity-guard/artifacts/demo.mp4 b/scientific-bounty-reviewer-capacity-guard/artifacts/demo.mp4
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diff --git a/scientific-bounty-reviewer-capacity-guard/artifacts/reviewer-capacity-report.md b/scientific-bounty-reviewer-capacity-guard/artifacts/reviewer-capacity-report.md
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+# Scientific bounty reviewer capacity report
+
+## BIO-42: Biomarker scoring challenge
+Decision: ASSIGN_PANEL
+Eligible reviewers: r-ada, r-lin
+Next step: assign the listed reviewers and open the review window
+
+## MAT-11: Low heat cement materials challenge
+Decision: HOLD_ASSIGNMENT
+Eligible reviewers: r-ivy
+Next step: hold assignment until coverage and capacity are fixed
+Blockers:
+- not enough eligible reviewers
+- conflicts: r-noah
+- overloaded: r-mira
+
+## QNT-7: Quantum noise reduction challenge
+Decision: HOLD_ASSIGNMENT
+Eligible reviewers: r-june
+Next step: hold assignment until coverage and capacity are fixed
+Blockers:
+- not enough eligible reviewers
+- missing expertise: quantum, signal-processing
+- stale training: r-sam
diff --git a/scientific-bounty-reviewer-capacity-guard/artifacts/reviewer-capacity-results.json b/scientific-bounty-reviewer-capacity-guard/artifacts/reviewer-capacity-results.json
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+[
+  {
+    "challengeId": "BIO-42",
+    "title": "Biomarker scoring challenge",
+    "decision": "ASSIGN_PANEL",
+    "eligibleReviewers": [
+      "r-ada",
+      "r-lin"
+    ],
+    "missingExpertise": [],
+    "blockers": [],
+    "nextStep": "assign the listed reviewers and open the review window"
+  },
+  {
+    "challengeId": "MAT-11",
+    "title": "Low heat cement materials challenge",
+    "decision": "HOLD_ASSIGNMENT",
+    "eligibleReviewers": [
+      "r-ivy"
+    ],
+    "missingExpertise": [],
+    "blockers": [
+      "not enough eligible reviewers",
+      "conflicts: r-noah",
+      "overloaded: r-mira"
+    ],
+    "nextStep": "hold assignment until coverage and capacity are fixed"
+  },
+  {
+    "challengeId": "QNT-7",
+    "title": "Quantum noise reduction challenge",
+    "decision": "HOLD_ASSIGNMENT",
+    "eligibleReviewers": [
+      "r-june"
+    ],
+    "missingExpertise": [
+      "quantum",
+      "signal-processing"
+    ],
+    "blockers": [
+      "not enough eligible reviewers",
+      "missing expertise: quantum, signal-processing",
+      "stale training: r-sam"
+    ],
+    "nextStep": "hold assignment until coverage and capacity are fixed"
+  }
+]
\ No newline at end of file
diff --git a/scientific-bounty-reviewer-capacity-guard/demo.js b/scientific-bounty-reviewer-capacity-guard/demo.js
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+const fs = require("fs");
+const path = require("path");
+const challenges = require("./sample-data.json");
+const { evaluatePortfolio, renderMarkdownReport } = require("./index");
+
+const artifactsDir = path.join(__dirname, "artifacts");
+fs.mkdirSync(artifactsDir, { recursive: true });
+
+const results = evaluatePortfolio(challenges);
+fs.writeFileSync(path.join(artifactsDir, "reviewer-capacity-results.json"), JSON.stringify(results, null, 2));
+fs.writeFileSync(path.join(artifactsDir, "reviewer-capacity-report.md"), renderMarkdownReport(results));
+
+console.log(renderMarkdownReport(results));
diff --git a/scientific-bounty-reviewer-capacity-guard/index.js b/scientific-bounty-reviewer-capacity-guard/index.js
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+const REQUIRED_REVIEWERS = 2;
+
+function scoreChallenge(challenge) {
+  const requiredExpertise = new Set(challenge.requiredExpertise || []);
+  const reviewers = challenge.reviewers || [];
+
+  const eligible = reviewers.filter((reviewer) => {
+    const hasConflict = (reviewer.conflicts || []).includes(challenge.id);
+    const isOverloaded = reviewer.activeReviews >= reviewer.maxActiveReviews;
+    const coversExpertise = (reviewer.expertise || []).some((item) => requiredExpertise.has(item));
+    return !hasConflict && !isOverloaded && reviewer.trainingCurrent && reviewer.available;
+  });
+
+  const coveredExpertise = new Set();
+  for (const reviewer of eligible) {
+    for (const item of reviewer.expertise || []) {
+      if (requiredExpertise.has(item)) coveredExpertise.add(item);
+    }
+  }
+
+  const missingExpertise = [...requiredExpertise].filter((item) => !coveredExpertise.has(item));
+  const overloaded = reviewers.filter((reviewer) => reviewer.activeReviews >= reviewer.maxActiveReviews);
+  const conflicted = reviewers.filter((reviewer) => (reviewer.conflicts || []).includes(challenge.id));
+  const staleTraining = reviewers.filter((reviewer) => !reviewer.trainingCurrent);
+
+  const blockers = [];
+  if (eligible.length < REQUIRED_REVIEWERS) blockers.push("not enough eligible reviewers");
+  if (missingExpertise.length) blockers.push(`missing expertise: ${missingExpertise.join(", ")}`);
+  if (conflicted.length) blockers.push(`conflicts: ${conflicted.map((r) => r.id).join(", ")}`);
+  if (overloaded.length) blockers.push(`overloaded: ${overloaded.map((r) => r.id).join(", ")}`);
+  if (staleTraining.length) blockers.push(`stale training: ${staleTraining.map((r) => r.id).join(", ")}`);
+
+  let decision = "ASSIGN_PANEL";
+  if (eligible.length < REQUIRED_REVIEWERS || missingExpertise.length) {
+    decision = "HOLD_ASSIGNMENT";
+  } else if (conflicted.length || overloaded.length || staleTraining.length) {
+    decision = "REBALANCE_PANEL";
+  }
+
+  return {
+    challengeId: challenge.id,
+    title: challenge.title,
+    decision,
+    eligibleReviewers: eligible.map((reviewer) => reviewer.id),
+    missingExpertise,
+    blockers,
+    nextStep: nextStepFor(decision),
+  };
+}
+
+function nextStepFor(decision) {
+  if (decision === "ASSIGN_PANEL") return "assign the listed reviewers and open the review window";
+  if (decision === "REBALANCE_PANEL") return "rebalance reviewer load or replace conflicted reviewers";
+  return "hold assignment until coverage and capacity are fixed";
+}
+
+function evaluatePortfolio(challenges) {
+  return challenges.map(scoreChallenge);
+}
+
+function renderMarkdownReport(results) {
+  const lines = ["# Scientific bounty reviewer capacity report", ""];
+  for (const result of results) {
+    lines.push(`## ${result.challengeId}: ${result.title}`);
+    lines.push(`Decision: ${result.decision}`);
+    lines.push(`Eligible reviewers: ${result.eligibleReviewers.join(", ") || "none"}`);
+    lines.push(`Next step: ${result.nextStep}`);
+    if (result.blockers.length) {
+      lines.push("Blockers:");
+      for (const blocker of result.blockers) lines.push(`- ${blocker}`);
+    }
+    lines.push("");
+  }
+  return lines.join("\n");
+}
+
+module.exports = {
+  evaluatePortfolio,
+  renderMarkdownReport,
+  scoreChallenge,
+};
diff --git a/scientific-bounty-reviewer-capacity-guard/sample-data.json b/scientific-bounty-reviewer-capacity-guard/sample-data.json
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+++ b/scientific-bounty-reviewer-capacity-guard/sample-data.json
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+[
+  {
+    "id": "BIO-42",
+    "title": "Biomarker scoring challenge",
+    "requiredExpertise": ["bioinformatics", "statistics"],
+    "reviewers": [
+      {
+        "id": "r-ada",
+        "expertise": ["bioinformatics"],
+        "activeReviews": 1,
+        "maxActiveReviews": 4,
+        "conflicts": [],
+        "trainingCurrent": true,
+        "available": true
+      },
+      {
+        "id": "r-lin",
+        "expertise": ["statistics", "ml"],
+        "activeReviews": 2,
+        "maxActiveReviews": 4,
+        "conflicts": [],
+        "trainingCurrent": true,
+        "available": true
+      }
+    ]
+  },
+  {
+    "id": "MAT-11",
+    "title": "Low heat cement materials challenge",
+    "requiredExpertise": ["materials", "climate"],
+    "reviewers": [
+      {
+        "id": "r-mira",
+        "expertise": ["materials"],
+        "activeReviews": 4,
+        "maxActiveReviews": 4,
+        "conflicts": [],
+        "trainingCurrent": true,
+        "available": true
+      },
+      {
+        "id": "r-noah",
+        "expertise": ["climate"],
+        "activeReviews": 1,
+        "maxActiveReviews": 3,
+        "conflicts": ["MAT-11"],
+        "trainingCurrent": true,
+        "available": true
+      },
+      {
+        "id": "r-ivy",
+        "expertise": ["materials", "climate"],
+        "activeReviews": 1,
+        "maxActiveReviews": 3,
+        "conflicts": [],
+        "trainingCurrent": true,
+        "available": true
+      }
+    ]
+  },
+  {
+    "id": "QNT-7",
+    "title": "Quantum noise reduction challenge",
+    "requiredExpertise": ["quantum", "signal-processing"],
+    "reviewers": [
+      {
+        "id": "r-sam",
+        "expertise": ["quantum"],
+        "activeReviews": 2,
+        "maxActiveReviews": 3,
+        "conflicts": [],
+        "trainingCurrent": false,
+        "available": true
+      },
+      {
+        "id": "r-june",
+        "expertise": ["statistics"],
+        "activeReviews": 0,
+        "maxActiveReviews": 2,
+        "conflicts": [],
+        "trainingCurrent": true,
+        "available": true
+      }
+    ]
+  }
+]
diff --git a/scientific-bounty-reviewer-capacity-guard/test.js b/scientific-bounty-reviewer-capacity-guard/test.js
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+const assert = require("assert");
+const challenges = require("./sample-data.json");
+const { evaluatePortfolio } = require("./index");
+
+const results = evaluatePortfolio(challenges);
+const byId = Object.fromEntries(results.map((result) => [result.challengeId, result]));
+
+assert.strictEqual(byId["BIO-42"].decision, "ASSIGN_PANEL");
+assert.deepStrictEqual(byId["BIO-42"].eligibleReviewers, ["r-ada", "r-lin"]);
+
+assert.strictEqual(byId["MAT-11"].decision, "HOLD_ASSIGNMENT");
+assert.ok(byId["MAT-11"].blockers.some((blocker) => blocker.includes("conflicts")));
+assert.ok(byId["MAT-11"].blockers.some((blocker) => blocker.includes("overloaded")));
+
+assert.strictEqual(byId["QNT-7"].decision, "HOLD_ASSIGNMENT");
+assert.deepStrictEqual(byId["QNT-7"].missingExpertise, ["quantum", "signal-processing"]);
+
+console.log("scientific bounty reviewer capacity guard tests passed");