Remove FloatBarrier injection, add figure placement rules to writer prompt

FloatBarrier approach was too rigid — figures piling up on a blank page
before References. Instead, writer agent is now responsible for checking
figure placement after every edit:
- No blank pages with only figures
- No figures after the last section
- Figures appear near their reference context
- Multi-panel figures use figure* in multi-column templates

Writer prompt: added "Figure Placement Rules" section with concrete fixes
(move figure earlier, reduce height, use [!htbp], etc.)

Reverted _ensure_clearpage_before_bibliography to simple \clearpage only.
Cleaned up euromlsys template (removed placeins/FloatBarrier).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: JihaoXin

ark/execution.py

@@ -725,54 +725,30 @@ def _enforce_page_count(self, context: str = "post-writing") -> bool:
                 return True
 
     def _ensure_clearpage_before_bibliography(self):
-        """Ensure \\FloatBarrier + \\clearpage before \\bibliography in main.tex.
+        """Ensure \\clearpage before \\bibliography in main.tex.
 
-        FloatBarrier forces all pending figures to be placed within the body
-        (prevents them from floating past References). clearpage starts a new
-        page for References. Both are injected programmatically.
+        This guarantees References starts on a new page, separate from body.
         """
         main_tex = self.latex_dir / "main.tex"
         if not main_tex.exists():
             return
         try:
             content = main_tex.read_text()
-            changed = False
-
-            # Ensure \usepackage{placeins} is in preamble (for \FloatBarrier)
-            if r'\usepackage{placeins}' not in content:
-                # Insert after last \usepackage line in preamble
-                import re
-                last_pkg = list(re.finditer(r'\\usepackage(\[.*?\])?\{.*?\}', content))
-                if last_pkg:
-                    insert_pos = last_pkg[-1].end()
-                    content = content[:insert_pos] + '\n\\usepackage{placeins}' + content[insert_pos:]
-                    changed = True
-
             marker = r'\bibliography{'
             if marker not in content:
                 return
-
-            # Build the correct pre-bibliography block
-            pre_bib = '\\FloatBarrier\n\\clearpage\n'
-
-            # Check if already correct
-            if pre_bib + marker in content:
-                if changed:
-                    main_tex.write_text(content)
-                return
-
-            # Remove any existing partial insertions and rebuild
+            # Clean up any old FloatBarrier injections
             content = content.replace('\\FloatBarrier\n\\clearpage\n' + marker, marker)
             content = content.replace('\\FloatBarrier\n' + marker, marker)
-            content = content.replace('\\clearpage\n' + marker, marker)
-            content = content.replace('\\clearpage\n\n' + marker, marker)
-
-            # Insert FloatBarrier + clearpage before bibliography
-            content = content.replace(marker, pre_bib + marker)
+            # Check if \clearpage already precedes \bibliography
+            if '\\clearpage\n' + marker in content or '\\clearpage\n\n' + marker in content:
+                return
+            # Insert \clearpage before \bibliography
+            content = content.replace(marker, '\\clearpage\n' + marker)
             main_tex.write_text(content)
-            self.log("Injected \\FloatBarrier + \\clearpage before \\bibliography", "INFO")
+            self.log("Injected \\clearpage before \\bibliography", "INFO")
         except Exception as e:
-            self.log(f"Failed to inject FloatBarrier/clearpage: {e}", "WARN")
+            self.log(f"Failed to inject \\clearpage: {e}", "WARN")
 
     def _run_writing_phase(self, action_plan: dict, prior_context: str = ""):
         """Execute writing phase for all writing tasks."""

ark/templates/agents/writer.prompt

@@ -62,6 +62,19 @@ The paper body (excluding references and appendix) has a strict page target:
 
 **Always ensure `\clearpage` appears before `\bibliography`** so references start on a new page.
 
+## Figure Placement Rules (MUST check after every edit)
+
+After every modification, compile and check that:
+1. **No blank pages with only figures** — if a figure can't fit on the current page, it may float to a later page. If this creates a page with only figure(s) and no text, fix it by:
+   - Moving the `\begin{figure}` declaration earlier in the text
+   - Reducing figure height with `\includegraphics[width=...,height=...]`
+   - Using `[!htbp]` placement specifier instead of `[t]`
+2. **No figures after the last section** — all figures must appear within or between body sections, never between the last section and `\clearpage`/References
+3. **Figures match their context** — a figure referenced in Section 3 should appear on or near Section 3's pages, not 2 pages later
+4. **Multi-panel figures use correct environment** — figures with 2+ panels (side-by-side) should use `\begin{figure*}` (full width) in multi-column templates, so fonts are readable
+
+If you see layout issues after compiling, fix them before finishing.
+
 **Compression strategies** (in order of priority):
 1. Move detailed ablations, sensitivity analyses, and per-category breakdowns to `\appendix`
 2. Merge Discussion and Conclusion into one section

venue_templates/euromlsys/main.tex

@@ -4,8 +4,6 @@
 \renewcommand\footnotetextcopyrightpermission[1]{}
 \pagestyle{plain}
 
-\usepackage{placeins}
-
 \begin{document}
 
 \title{Paper Title}
@@ -32,7 +30,6 @@ \section{Experiments}
 
 \section{Conclusion}
 
-\FloatBarrier
 \clearpage
 \bibliographystyle{ACM-Reference-Format}
 \bibliography{references}