fix(mcp): validate navigation pagination and fix recent_activity project display (#915)

Signed-off-by: phernandez <paul@basicmachines.co>
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/basic_memory/mcp/tools/build_context.py

@@ -209,6 +209,18 @@ async def build_context(
     Raises:
         ToolError: If project doesn't exist or depth parameter is invalid
     """
+    # Validate pagination arguments before they reach the context service.
+    # Trigger: page < 1 or page_size < 1 (e.g. page_size=0 or negative).
+    # Why: a non-positive page_size flows into context_service as limit, where the
+    #      primary slice does primary = primary[:limit] — so limit=0 truncates the
+    #      requested entity to [] and the caller's valid memory:// lookup silently
+    #      returns primary_count=0. Mirrors recent_activity's guard for consistency.
+    # Outcome: caller gets an explicit ValueError instead of a dropped primary result.
+    if page < 1:
+        raise ValueError(f"page must be >= 1, got {page}")
+    if page_size < 1:
+        raise ValueError(f"page_size must be >= 1, got {page_size}")
+
     # Detect project from memory URL prefix before routing.
     # project_id routes by external UUID, so it bypasses URL discovery entirely.
     if project is None and project_id is None:

src/basic_memory/mcp/tools/recent_activity.py

@@ -300,14 +300,20 @@ async def recent_activity(
     else:
         # Project-Specific Mode: Get activity for specific project
         # Uses get_project_client() for per-project routing (local vs cloud)
-        logger.info(
-            f"Getting recent activity from project {resolved_project}: type={type}, depth={depth}, timeframe={timeframe}"
-        )
-
         async with get_project_client(resolved_project, context=context, project_id=project_id) as (
             client,
             active_project,
         ):
+            # Trigger: caller routed by project_id (a UUID), so resolved_project holds the
+            #          raw UUID rather than a human-readable name.
+            # Why: active_project.name is the canonical, display-safe project name regardless
+            #      of whether routing was by name or by external_id.
+            # Outcome: logs and the formatted text header always show the project name.
+            logger.info(
+                f"Getting recent activity from project {active_project.name}: "
+                f"type={type}, depth={depth}, timeframe={timeframe}"
+            )
+
             response = await call_get(
                 client,
                 f"/v2/projects/{active_project.external_id}/memory/recent",
@@ -319,7 +325,7 @@ async def recent_activity(
                 return _extract_recent_rows(activity_data)
 
             # Format project-specific mode output
-            return _format_project_output(resolved_project, activity_data, timeframe, type, page)
+            return _format_project_output(active_project.name, activity_data, timeframe, type, page)
 
 
 async def _get_project_activity(

src/basic_memory/mcp/tools/search.py

@@ -866,6 +866,19 @@ async def search_notes(
         # Explicit project specification
         results = await search_notes("project planning", project="my-project")
     """
+    # Validate pagination arguments before they reach the API/repository layer.
+    # Trigger: page < 1 or page_size < 1 (e.g. page_size=0 or a negative slice).
+    # Why: a non-positive page_size yields zero rows yet the router computes
+    #      has_more = offset + len(results) < total, returning a misleading
+    #      has_more=True with no reachable page; a negative page_size becomes an
+    #      uncapped SQLite LIMIT. Mirrors recent_activity's guard so all navigation
+    #      tools reject invalid pagination consistently.
+    # Outcome: caller gets an explicit ValueError instead of a silent bad payload.
+    if page < 1:
+        raise ValueError(f"page must be >= 1, got {page}")
+    if page_size < 1:
+        raise ValueError(f"page_size must be >= 1, got {page_size}")
+
     # Avoid mutable-default-argument footguns. Treat None as "no filter".
     # Lowercase note_types so "Chapter" matches the stored "chapter".
     note_types = [t.lower() for t in note_types] if note_types else []