fix(slack): comprehensive mrkdwn formatting for send, edit, and tool paths by dashed · Pull Request #3715 · NousResearch/hermes-agent

dashed · 2026-03-29T12:55:51Z

Summary

Normalizes markdown-to-Slack-mrkdwn conversion across all message delivery paths (gateway send, streaming edit, tool-layer direct send). Fixes 6 bugs found during audit against the Slack mrkdwn spec.

Bugs fixed

Blockquote markers escaped — > at line start was escaped to >, breaking blockquote rendering. Now protected with placeholders before escaping.
edit_message() sent raw markdown — streamed/edited messages showed literal **bold** and [links](url). Now calls format_message() before chat_update().
***bold italic*** produced invalid mrkdwn — triple-star was consumed by the bold regex, producing **text**. Added dedicated triple-star step producing *_text_*.
HTML entity double-escaping — pre-escaped & became &amp;. Added unescape-before-escape to make the operation idempotent.
URLs with parentheses truncated — Wikipedia-style links like Foo_(bar) were cut short. Replaced URL regex with balanced-parentheses matching.
Step comment numbering — duplicate step numbers after inserting new steps. Renumbered 1-13.

Other changes

Explicitly set mrkdwn: True on chat.postMessage payloads
Protect existing Slack entities (<@user>, <#channel>, <!here>, <!subteam^...>, <!date^...>) from escaping
Handle CommonMark angle-bracket link syntax [text](<url>)
Use idiomatic reversed(dict) instead of reversed(list(dict.keys()))

Test coverage

47 unit tests in TestFormatMessage covering all formatting conversions, entity preservation, edge cases
4 unit tests in TestEditMessage for edit formatting
8 e2e tests in TestEditMessageStreamingPipeline simulating streaming edits
7 e2e tests in TestMessageSplitting for the gateway send path
5 e2e tests in TestSendToPlatformChunking for the tool-layer send path

140 tests pass, 0 failures.

Test plan

uv run --extra dev --extra messaging pytest tests/gateway/test_slack.py tests/tools/test_send_message_tool.py -v

All unit tests for format_message() pass
All e2e tests for send, edit, and tool paths pass
Existing tests unaffected (no regressions)
Reviewed against Slack mrkdwn spec

Blockquote `>` prefixes at line start were being escaped to `>` by the control character escaping step, breaking Slack blockquote rendering. Protect them with placeholders before escaping, matching how entities and code blocks are already handled. Renumber step comments to be sequential (1-12). Add unit and e2e tests for blockquote formatting.

…dits edit_message() was passing raw markdown content to chat_update(), causing streamed and edited Slack messages to display literal **bold**, [links](url), and ## headers instead of rendered mrkdwn. Call format_message() before sending, matching the pattern used by send() and TelegramAdapter.edit_message(). Add unit and e2e tests covering the edit formatting pipeline.

The bold regex was consuming ***text*** and producing **text** (invalid Slack mrkdwn) because the inner *text* was stashed behind a placeholder before the italic pass could see it. Add a dedicated triple-star step before bold conversion that produces *_text_* (Slack bold wrapping italic). Add unit and e2e tests for bold+italic across send, edit, and tool paths.

Input already containing &, <, or > was being double-escaped (e.g. & → &amp;). Unescape known HTML entities before re-escaping to make the operation idempotent. Add unit and e2e tests verifying pre-escaped content survives send, edit, and tool paths.

…kdwn tests Fix link regex to support one level of balanced parentheses in URLs (e.g. Wikipedia links). Add comprehensive test coverage for Slack entity preservation (<!channel>, <!everyone>, <!subteam^...>, <!date^...>, <#C...>), code-only messages, multiline mixed formatting, asterisk lists, bold-in-link labels, ampersand-in-URL query strings, and emoji shortcode passthrough.

…tion Python 3.8+ supports reversed() directly on dicts. Remove unnecessary list() materialization of placeholder keys.

@user

Fixes blockquote > escaping, edit_message raw markdown, ***bold italic*** handling, HTML entity double-escaping (&amp;), Wikipedia URL parens truncation, and step numbering format. Also adds format_message to the tool-layer _send_to_platform for consistent formatting across all delivery paths. Changes: - Protect Slack entities (<@user>, <https://...|label>, <!here>) from escaping passes - Protect blockquote > markers before HTML entity escaping - Unescape-before-escape for idempotent HTML entity handling - ***bold italic*** → *_text_* conversion (before **bold** pass) - URL regex upgraded to handle balanced parentheses - mrkdwn:True flag on chat_postMessage payloads - format_message applied in edit_message and send_message_tool - 52 new tests (format, edit, streaming, splitting, tool chunking) - Use reversed(dict) idiom for placeholder restoration Based on PR #3715 by dashed, cherry-picked onto current main.

@user

Fixes blockquote > escaping, edit_message raw markdown, ***bold italic*** handling, HTML entity double-escaping (&amp;), Wikipedia URL parens truncation, and step numbering format. Also adds format_message to the tool-layer _send_to_platform for consistent formatting across all delivery paths. Changes: - Protect Slack entities (<@user>, <https://...|label>, <!here>) from escaping passes - Protect blockquote > markers before HTML entity escaping - Unescape-before-escape for idempotent HTML entity handling - ***bold italic*** → *_text_* conversion (before **bold** pass) - URL regex upgraded to handle balanced parentheses - mrkdwn:True flag on chat_postMessage payloads - format_message applied in edit_message and send_message_tool - 52 new tests (format, edit, streaming, splitting, tool chunking) - Use reversed(dict) idiom for placeholder restoration Based on PR #3715 by dashed, cherry-picked onto current main.

teknium1 · 2026-04-09T21:07:55Z

Merged via PR #6809 as part of a consolidated Slack adapter improvement. Your contribution was all 7 commits cherry-picked. Your authorship is preserved in git history. Thank you @dashed for your work on this!

@user

Fixes blockquote > escaping, edit_message raw markdown, ***bold italic*** handling, HTML entity double-escaping (&amp;), Wikipedia URL parens truncation, and step numbering format. Also adds format_message to the tool-layer _send_to_platform for consistent formatting across all delivery paths. Changes: - Protect Slack entities (<@user>, <https://...|label>, <!here>) from escaping passes - Protect blockquote > markers before HTML entity escaping - Unescape-before-escape for idempotent HTML entity handling - ***bold italic*** → *_text_* conversion (before **bold** pass) - URL regex upgraded to handle balanced parentheses - mrkdwn:True flag on chat_postMessage payloads - format_message applied in edit_message and send_message_tool - 52 new tests (format, edit, streaming, splitting, tool chunking) - Use reversed(dict) idiom for placeholder restoration Based on PR NousResearch#3715 by dashed, cherry-picked onto current main.

@user

Fixes blockquote > escaping, edit_message raw markdown, ***bold italic*** handling, HTML entity double-escaping (&amp;), Wikipedia URL parens truncation, and step numbering format. Also adds format_message to the tool-layer _send_to_platform for consistent formatting across all delivery paths. Changes: - Protect Slack entities (<@user>, <https://...|label>, <!here>) from escaping passes - Protect blockquote > markers before HTML entity escaping - Unescape-before-escape for idempotent HTML entity handling - ***bold italic*** → *_text_* conversion (before **bold** pass) - URL regex upgraded to handle balanced parentheses - mrkdwn:True flag on chat_postMessage payloads - format_message applied in edit_message and send_message_tool - 52 new tests (format, edit, streaming, splitting, tool chunking) - Use reversed(dict) idiom for placeholder restoration Based on PR NousResearch#3715 by dashed, cherry-picked onto current main.

@user

Fixes blockquote > escaping, edit_message raw markdown, ***bold italic*** handling, HTML entity double-escaping (&amp;), Wikipedia URL parens truncation, and step numbering format. Also adds format_message to the tool-layer _send_to_platform for consistent formatting across all delivery paths. Changes: - Protect Slack entities (<@user>, <https://...|label>, <!here>) from escaping passes - Protect blockquote > markers before HTML entity escaping - Unescape-before-escape for idempotent HTML entity handling - ***bold italic*** → *_text_* conversion (before **bold** pass) - URL regex upgraded to handle balanced parentheses - mrkdwn:True flag on chat_postMessage payloads - format_message applied in edit_message and send_message_tool - 52 new tests (format, edit, streaming, splitting, tool chunking) - Use reversed(dict) idiom for placeholder restoration Based on PR NousResearch#3715 by dashed, cherry-picked onto current main.

@user

Fixes blockquote > escaping, edit_message raw markdown, ***bold italic*** handling, HTML entity double-escaping (&amp;), Wikipedia URL parens truncation, and step numbering format. Also adds format_message to the tool-layer _send_to_platform for consistent formatting across all delivery paths. Changes: - Protect Slack entities (<@user>, <https://...|label>, <!here>) from escaping passes - Protect blockquote > markers before HTML entity escaping - Unescape-before-escape for idempotent HTML entity handling - ***bold italic*** → *_text_* conversion (before **bold** pass) - URL regex upgraded to handle balanced parentheses - mrkdwn:True flag on chat_postMessage payloads - format_message applied in edit_message and send_message_tool - 52 new tests (format, edit, streaming, splitting, tool chunking) - Use reversed(dict) idiom for placeholder restoration Based on PR NousResearch#3715 by dashed, cherry-picked onto current main.

@user

Fixes blockquote > escaping, edit_message raw markdown, ***bold italic*** handling, HTML entity double-escaping (&amp;), Wikipedia URL parens truncation, and step numbering format. Also adds format_message to the tool-layer _send_to_platform for consistent formatting across all delivery paths. Changes: - Protect Slack entities (<@user>, <https://...|label>, <!here>) from escaping passes - Protect blockquote > markers before HTML entity escaping - Unescape-before-escape for idempotent HTML entity handling - ***bold italic*** → *_text_* conversion (before **bold** pass) - URL regex upgraded to handle balanced parentheses - mrkdwn:True flag on chat_postMessage payloads - format_message applied in edit_message and send_message_tool - 52 new tests (format, edit, streaming, splitting, tool chunking) - Use reversed(dict) idiom for placeholder restoration Based on PR NousResearch#3715 by dashed, cherry-picked onto current main.

@user

Fixes blockquote > escaping, edit_message raw markdown, ***bold italic*** handling, HTML entity double-escaping (&amp;), Wikipedia URL parens truncation, and step numbering format. Also adds format_message to the tool-layer _send_to_platform for consistent formatting across all delivery paths. Changes: - Protect Slack entities (<@user>, <https://...|label>, <!here>) from escaping passes - Protect blockquote > markers before HTML entity escaping - Unescape-before-escape for idempotent HTML entity handling - ***bold italic*** → *_text_* conversion (before **bold** pass) - URL regex upgraded to handle balanced parentheses - mrkdwn:True flag on chat_postMessage payloads - format_message applied in edit_message and send_message_tool - 52 new tests (format, edit, streaming, splitting, tool chunking) - Use reversed(dict) idiom for placeholder restoration Based on PR NousResearch#3715 by dashed, cherry-picked onto current main.

@user

Fixes blockquote > escaping, edit_message raw markdown, ***bold italic*** handling, HTML entity double-escaping (&amp;), Wikipedia URL parens truncation, and step numbering format. Also adds format_message to the tool-layer _send_to_platform for consistent formatting across all delivery paths. Changes: - Protect Slack entities (<@user>, <https://...|label>, <!here>) from escaping passes - Protect blockquote > markers before HTML entity escaping - Unescape-before-escape for idempotent HTML entity handling - ***bold italic*** → *_text_* conversion (before **bold** pass) - URL regex upgraded to handle balanced parentheses - mrkdwn:True flag on chat_postMessage payloads - format_message applied in edit_message and send_message_tool - 52 new tests (format, edit, streaming, splitting, tool chunking) - Use reversed(dict) idiom for placeholder restoration Based on PR NousResearch#3715 by dashed, cherry-picked onto current main.

dashed marked this pull request as ready for review March 29, 2026 12:56

dashed mentioned this pull request Mar 29, 2026

dashed/my-hermes: custom fork integration branch dashed/hermes-agent#2

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7 tasks

dashed force-pushed the fix/slack-mrkdwn-formatting branch 3 times, most recently from cefa270 to ad1074d Compare April 4, 2026 17:28

dashed and others added 7 commits April 7, 2026 07:36

fix(slack): normalize mrkdwn formatting for direct sends

ed73a52

refactor(slack): use idiomatic reversed(dict) for placeholder restora…

e60fe92

…tion Python 3.8+ supports reversed() directly on dicts. Remove unnecessary list() materialization of placeholder keys.

dashed force-pushed the fix/slack-mrkdwn-formatting branch from ad1074d to e60fe92 Compare April 7, 2026 11:41

teknium1 mentioned this pull request Apr 9, 2026

feat(slack): consolidated Slack adapter improvements — 7 community PRs salvaged #6809

Merged

teknium1 closed this Apr 9, 2026

teknium1 mentioned this pull request Apr 9, 2026

fix(slack): formatting consistency, table conversion, thread reply fix #2525

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fix(slack): comprehensive mrkdwn formatting for send, edit, and tool paths#3715

fix(slack): comprehensive mrkdwn formatting for send, edit, and tool paths#3715
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dashed commented Mar 29, 2026

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dashed commented Mar 29, 2026

Summary

Bugs fixed

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teknium1 commented Apr 9, 2026

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