Make task context page packing logarithmic

tests/test_mcp_server.py

@@ -26,11 +26,12 @@ from docforge.mcp_server import (
     CONTENT_WARNING,
     PROPOSAL_TOOLS,
     READ_TOOLS,
+    SERVER_VERSION,
     DocForgeService,
     _create_bound_server,
     create_server,
 )
-from docforge.project import Project
+from docforge.project import Project, project_root_fingerprint
 from docforge.viewer_manager import ViewerManager
 
 ROOT = Path(__file__).resolve().parents[1]
@@ -416,6 +417,93 @@ class DocForgeMcpTests(unittest.IsolatedAsyncioTestCase):
                 8_000,
             )
 
+    def test_dense_task_context_page_packing_is_logarithmic(self) -> None:
+        with tempfile.TemporaryDirectory() as directory:
+            root = self.copy_fixture("alpha", Path(directory))
+            descriptor = root / ".docforge" / "project.toml"
+            descriptor.write_text(
+                descriptor.read_text(encoding="utf-8")
+                .replace("max_results = 20", "max_results = 1000")
+                .replace(
+                    "max_context_tokens = 2000",
+                    "max_context_tokens = 2000\nmax_tool_output_chars = 20000",
+                ),
+                encoding="utf-8",
+            )
+            project = Project.open(root)
+            service = DocForgeService(project, capability_mode_name="read")
+            capsule = {
+                "schema_version": 1,
+                "plan": {
+                    "effective_policy_hash": "1" * 64,
+                    "request_hash": "2" * 64,
+                    "plan_hash": "3" * 64,
+                },
+                "generation": {"index_schema_version": 3},
+                "evidence": [
+                    {
+                        "node_id": f"node.{index:04d}",
+                        "content": "bounded evidence " * 40,
+                    }
+                    for index in range(1_000)
+                ],
+                "gaps": [],
+                "omissions": [],
+                "collection_hash": "4" * 64,
+                "capsule_hash": "5" * 64,
+                "state": "complete",
+                "summary": {"evidence_count": 1_000},
+            }
+            result = {
+                "status": "ok",
+                "project_id": project.descriptor.project_id,
+                "project_root_fingerprint": project_root_fingerprint(project.descriptor.root),
+                "adapter": project.descriptor.adapter,
+                "revision": "test-revision",
+                "source_hash": "6" * 64,
+                "capsule": capsule,
+            }
+
+            with mock.patch.object(
+                service,
+                "_encoded_length",
+                wraps=service._encoded_length,
+            ) as encoded_length:
+                page = service._page_task_context_result(
+                    result,
+                    selected_limit=1_000,
+                    cursor=None,
+                )
+
+            pagination = page["pagination"]
+            self.assertGreater(pagination["returned_count"], 0)
+            self.assertLess(pagination["returned_count"], 1_000)
+            returned_count = pagination["returned_count"]
+            self.assertEqual(
+                capsule["evidence"][:returned_count],
+                page["capsule"]["evidence"],
+            )
+            self.assertEqual([], page["capsule"]["omissions"])
+            self.assertEqual(
+                pagination["next_cursor"],
+                page["capsule"]["pagination"]["next_cursor"],
+            )
+            self.assertEqual(
+                returned_count,
+                page["capsule"]["summary"]["page_item_count"],
+            )
+            self.assertLessEqual(encoded_length.call_count, 11)
+            decorated = {
+                **page,
+                "server_version": SERVER_VERSION,
+                "content_warning": CONTENT_WARNING,
+                "staleness": "current",
+            }
+            self.assertLessEqual(
+                len(json.dumps(decorated, sort_keys=True, separators=(",", ":"))),
+                20_000,
+            )
+
     def test_task_context_default_page_clamps_to_small_project_limit(self) -> None:
         with tempfile.TemporaryDirectory() as directory:
             root = self.copy_fixture("alpha", Path(directory))