On Windows, opening a directory with O_RDONLY raises PermissionError.
Wrap the directory fsync in a try/except PermissionError — NTFS journals
metadata synchronously so the directory sync is unnecessary there.
Also adjust test assertions to expect 1 fsync call (file only) on
Windows vs 2 (file + directory) on POSIX.
On filesystems with write-back caching (rclone VFS, NFS, FUSE mounts)
the OS page cache may buffer recent session writes. If the process is
killed before the cache flushes, the most recent conversation turns are
silently lost — causing the agent to "forget" recent context and
respond to stale history on the next startup.
Changes:
- session/manager.py: add fsync=True option to save() that flushes the
file and its parent directory to durable storage. Add flush_all() that
re-saves every cached session with fsync. Default save() behavior is
unchanged (no fsync) to avoid performance regression in normal
operation.
- cli/commands.py: call agent.sessions.flush_all() in the gateway
shutdown finally block, after stopping heartbeat/cron/channels.
- tests/session/test_session_fsync.py: 8 tests covering fsync flag
behavior, flush_all with empty/multiple/errored sessions, and
data survival across simulated process restart.
- tests/cli/test_commands.py: add sessions attribute to _FakeAgentLoop
so the gateway health endpoint test passes with the new shutdown
flush.
Problem:
Modern LLMs (GPT-5.4, Claude, Gemini) produce markdown-heavy responses with
numbered lists, headers, and nested formatting. The Telegram channel's
_markdown_to_telegram_html() converter has gaps that leave these poorly
formatted:
1. Numbered lists (1. 2. 3.) have zero handling — sent as raw text
2. Headers (# Title) are stripped to plain text, losing visual hierarchy
3. Mid-stream edits send raw markdown (users see **bold** and ### headers
while the response generates, before the final HTML conversion)
Root Cause:
_markdown_to_telegram_html() handles bullets (- *) but skips numbered lists
entirely. Headers are stripped of # but not given any emphasis. The streaming
path in send_delta() sends buf.text as-is during mid-stream edits (plain
text, no parse_mode) — only the final _stream_end edit converts to HTML.
Fix:
1. Headers now render as <b>bold</b> in the final HTML (using placeholder
markers that survive HTML escaping, restored after all other processing)
2. Numbered lists are normalized (extra whitespace after the dot is cleaned)
3. New _strip_md_block() function strips markdown syntax for readable
plain-text preview during streaming mid-edits
The final _stream_end HTML conversion is unchanged — it still produces
full HTML with parse_mode=HTML. Only the intermediate edits are improved.
Tests:
Added 10 new tests covering:
- Headers converting to bold HTML
- Numbered list preservation and whitespace normalization
- Headers with HTML special characters
- Mixed formatting (headers + bullets + numbers + bold)
- _strip_md_block for inline formatting, headers, bullets, numbers, links
- Streaming mid-edit markdown stripping (initial send + edit)
When an MCP server restarts or a network connection drops between
tool calls, the existing session throws ClosedResourceError,
BrokenPipeError, ConnectionResetError, etc. Currently these are
caught as generic exceptions and returned as permanent failures
to the LLM, which then tells the user 'my tools are broken.'
This change adds a single automatic retry with a 1-second backoff
for transient connection-class errors in MCPToolWrapper,
MCPResourceWrapper, and MCPPromptWrapper. Non-transient errors
(ValueError, RuntimeError, McpError, etc.) are not retried.
The retry is conservative:
- Only 1 retry (not configurable, to keep the change minimal)
- Only for a specific set of connection-class exceptions
- Matched by exception class name to avoid importing anyio/etc.
- 1s sleep between attempts to allow the server to recover
- Clear logging distinguishes retried vs permanent failures
In production this eliminates most 'MCP tool call failed:
ClosedResourceError' noise when MCP bridge processes restart
(e.g. after config changes or OOM kills).
Tests: 22 new tests covering retry, exhaustion, non-transient
bypass, timeout bypass, and all three wrapper types.
Anthropic does not support assistant-message prefill and returns a 400
error when the conversation ends with an assistant turn. This commonly
happens when heartbeat/system messages accumulate trailing assistant
replies in the session history.
The _merge_consecutive method already handles same-role merging but did
not strip trailing assistant messages. The base provider's
_enforce_role_alternation (used by OpenAI-compat) does strip them, but
AnthropicProvider uses its own _merge_consecutive instead.
Add a trailing-assistant stripping loop to _merge_consecutive, matching
the behavior already present in _enforce_role_alternation.
Includes 7 new tests covering merge + strip behavior.
When a user sends /stop to interrupt an active agent turn, the task is
cancelled via CancelledError. Previously, the cancellation handler just
logged and re-raised, discarding any tool results and assistant messages
accumulated during the interrupted turn.
The runtime checkpoint mechanism already persists partial turn state
(assistant messages, completed tool results, pending tool calls) into
session metadata via _emit_checkpoint. However, this checkpoint was only
materialized into session history on the NEXT incoming message via
_restore_runtime_checkpoint — not at cancellation time.
Now the CancelledError handler in _dispatch calls
_restore_runtime_checkpoint immediately, so the partial context is
preserved in session history. This means the next message the user sends
will see all the work that was done before /stop, rather than starting
from scratch.
Fixes#2966
Includes 3 tests verifying checkpoint restoration on cancellation.
hussein1362andXubin Ren