fix(serve): honest overshoot notice when edges push a complete answer over budget (#2784)

graphify/serve.py

@@ -1087,11 +1087,29 @@ def _adj(n):
         # lost. Announcing "showing N of N nodes … among the 0 cut nodes" then
         # reads as a false truncation warning that teaches an agent to distrust a
         # complete answer and burn follow-up narrowing calls for nodes that were
-        # never cut (#2601). When every node is shown the answer is complete:
-        # return the full output with no banner rather than silently dropping
-        # edges under a misleading notice.
+        # never cut (#2601). When every node is shown the answer is complete, so
+        # edges are never dropped either (returning output[:cut_at] here would
+        # silently truncate them) — but that completeness guarantee is exactly
+        # why a query can quietly cost 4-6x its requested budget once the last
+        # node crosses the fit line (#2784): the check above only ever compared
+        # the FULL output (nodes+edges) against char_budget, so this branch was
+        # already known to be over budget, yet said nothing about it. Report the
+        # real size instead of silence — still the complete, non-truncated
+        # answer, just an honest one.
         if cut_count == 0:
-            return output
+            if len(output) <= char_budget:
+                return output
+            total_edges = sum(1 for l in lines if l.startswith("EDGE "))
+            est_tokens = len(output) // 3
+            return (
+                f"[i] Complete answer over budget: all {total_nodes} nodes and "
+                f"{total_edges} edges shown (~{est_tokens} tokens vs the "
+                f"requested ~{token_budget}-token budget). Edges are never "
+                f"dropped once every node fits, so this is already the full "
+                f"answer — raising --budget further will not shrink it. Narrow "
+                f"with context_filter=['call'] or use get_node for a specific "
+                f"symbol to reduce size instead.\n\n"
+            ) + output
         # Prominent notice at the TOP so a truncated answer can never be mistaken
         # for a complete one — silence used to read as absence (#BUG2). The
         # notice + end marker sit OUTSIDE char_budget by design (two bounded

tests/test_serve.py

@@ -1523,6 +1523,51 @@ def test_subgraph_to_text_no_banner_when_only_edges_overflow():
     assert len(edge_lines) == len(edges), "all edges must survive a complete answer"
 
 
+def test_subgraph_to_text_overshoot_notice_when_edges_exceed_budget():
+    """#2784: once every node fits, edges are never dropped (#2601) — but that
+    used to mean the char_budget check silently stopped applying, so a query
+    could cost 4-6x its requested budget with zero indication. The complete
+    answer must still be returned whole, but the overshoot must be visible and
+    must not repeat the "raise the budget" advice that caused the blow-up."""
+    import itertools
+
+    G = nx.Graph()
+    labels = [f"n{i}" for i in range(20)]
+    for lbl in labels:
+        G.add_node(lbl, label=lbl, source_file="f.py", source_location="L1", community="c")
+    edges = list(itertools.combinations(labels, 2))
+    for u, v in edges:
+        G.add_edge(u, v, relation="calls", confidence="high")
+    node_chars = len("\n".join(f"NODE {l} [src=f.py loc=L1 community=c]" for l in labels))
+    budget = (node_chars // 3) + 5  # fits every node, nowhere near every edge
+    text = _subgraph_to_text(G, set(G.nodes), edges, token_budget=budget)
+    node_lines = [l for l in text.splitlines() if l.startswith("NODE ")]
+    edge_lines = [l for l in text.splitlines() if l.startswith("EDGE ")]
+    assert len(node_lines) == len(labels)
+    assert len(edge_lines) == len(edges), "complete answer: edges must not be dropped"
+    assert "Complete answer over budget" in text
+    assert str(len(labels)) in text and str(len(edges)) in text
+    assert "raise" not in text.lower(), "must not repeat the advice that caused the overshoot"
+    assert "TRUNCATED" not in text and "truncated" not in text
+
+
+def test_subgraph_to_text_no_overshoot_notice_when_edges_fit_too():
+    """The honest-overshoot notice is additive: a complete answer that already
+    fits the budget must render exactly as before, with no notice at all."""
+    import itertools
+
+    G = nx.Graph()
+    labels = [f"n{i}" for i in range(3)]
+    for lbl in labels:
+        G.add_node(lbl, label=lbl, source_file="f.py", source_location="L1", community="c")
+    edges = list(itertools.combinations(labels, 2))
+    for u, v in edges:
+        G.add_edge(u, v, relation="calls", confidence="high")
+    text = _subgraph_to_text(G, set(G.nodes), edges, token_budget=2000)
+    assert "Complete answer over budget" not in text
+    assert "TRUNCATED" not in text and "truncated" not in text
+
+
 def test_subgraph_to_text_order_is_deterministic():
     """Equal-degree nodes render in a stable order regardless of set iteration."""
     G = nx.Graph()