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diff --git a/proofsearch/include/atp/core/term_bank.h b/proofsearch/include/atp/core/term_bank.h
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+/*
+ * richard-atp-engine: A saturation-based automated theorem prover for first-order logic.
+ * Copyright (C) 2026 Richard Qin
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+/// @file term_bank.h
+/// @brief Hash-consing term pool — guarantees structural sharing.
+
+#include "atp/core/symbol_table.h"
+#include "atp/core/term.h"
+#include "atp/core/types.h"
+
+#include <span>
+#include <unordered_map>
+#include <vector>
+
+namespace atp {
+
+/// Global term pool with hash-consing.
+/// Every structurally identical term maps to the same TermId.
+///
+/// Holds a reference to SymbolTable for variable detection.
+class TermBank {
+  public:
+    /// TermBank needs the SymbolTable to distinguish variables from constants
+    /// (both have 0 args, but SymbolKind differs).
+        explicit TermBank(SymbolTable& symbols) : symbols_(&symbols) {}
+
+    /// Create or retrieve a term. Returns the canonical TermId.
+    TermId makeTerm(SymbolId symbol, std::span<const TermId> args);
+
+    /// Create a variable term. Convenience for makeTerm(var, {}).
+    TermId makeVar(SymbolId var_symbol);
+
+    /// Look up a term by its ID.
+    [[nodiscard]] const Term& getTerm(TermId id) const;
+
+    /// Check if a TermId represents a variable (delegates to SymbolTable).
+    [[nodiscard]] bool isVariable(TermId id) const;
+
+    /// Total number of unique terms stored.
+    [[nodiscard]] size_t size() const;
+
+    /// Access the underlying SymbolTable.
+    [[nodiscard]] const SymbolTable& symbols() const { return *symbols_; }
+    [[nodiscard]] SymbolTable& mutableSymbols() { return *symbols_; }
+
+  private:
+    struct TermKey {
+        SymbolId symbol_;
+        std::vector<TermId> args_;
+
+        bool operator==(const TermKey& other) const = default;
+    };
+
+    struct TermKeyHash {
+        size_t operator()(const TermKey& key) const {
+            size_t seed = std::hash<uint32_t>{}(key.symbol_);
+            for (const TermId arg : key.args_) {
+                seed ^= std::hash<TermId>{}(arg) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
+            }
+            return seed;
+        }
+    };
+
+    SymbolTable* symbols_;
+    std::vector<Term> terms_;
+    std::unordered_map<TermKey, TermId, TermKeyHash> term_to_id_;
+};
+
+}  // namespace atp