Fix Slack notifications: 'fields' is not a Block Kit block type

[richard-devbot]

Problem

Slack notifications have never been deliverable. Both payload builders in src/notifications/index.js (formatSlackStageMessage, formatSlackTaskReportMessage) emit a block of:

{ type: 'fields', fields }

Block Kit has no fields block type — fields belong on a section block. Slack rejects the entire attachment:

Webhook post failed with status: 400. Body: invalid_attachments

Because the failure is at the attachment level, no part of the message is delivered. Notifications are also fire-and-forget by design (router.js), so this failed silently in normal operation.

Reproduction

Against a live Incoming Webhook, with RSTACK_SLACK_WEBHOOK set:

$ npx rstack-agents notify --test
[rstack] Configured channels: slack
  ✗ slack — Webhook post failed with status: 400. Body: invalid_attachments

After this change, same webhook:

$ npx rstack-agents notify --test
[rstack] Configured channels: slack
  ✓ slack

Message confirmed delivered to the channel.

Fix

Producer now emits type: 'section' with fields, which is the correct Block Kit shape.

The bogus type had propagated to every consumer, so each is updated to read fields off a section block while still tolerating the old 'fields' shape — that keeps any persisted or in-flight payloads converting correctly:

File	Role
src/notifications/index.js	producer — 2 sites
channels/teams.js	facts extraction
channels/discord.js	embed fields
channels/text.js	plain-text flattening

Verification

• Teams and Discord converters produce identical output to before the change (same 4 facts / 4 embed fields for a stage message with a cost detail).
• tests/notifications-channels.test.js, tests/harness-notifications.test.js, tests/notify-hook.test.js — 21/21 pass.
• The existing slackPayloadToText renders blocks as readable plain text test caught text.js, a consumer missed on the first pass — worth noting the suite did its job here.

Note for maintainers

Separately from this fix: nothing loads a project's .env into process.env. resolveChannels reads process.env and .rstack/notifications.json only, while core/harness/env-file.js is used solely by the Hub UI to edit keys. Following the docs/integrations/webhooks.md guidance to put RSTACK_SLACK_WEBHOOK in .env therefore does not enable the channel unless the variable is also exported into the real environment. Left out of scope here — happy to open a separate issue.

🤖 Generated with Claude Code

Summary by CodeRabbit

• Bug Fixes
  • Improved Slack notification formatting across Discord, Microsoft Teams, and text outputs.
  • Supports field content included in section blocks, including older or nonstandard Slack payloads.
  • Corrected generated Slack Block Kit formatting to use valid section blocks, ensuring fields display reliably.

[strix-security]

Strix Security Review

No security issues found.

_{Updated for d82f3c1.}

---

Reviewed by Strix
_{Re-run review · Configure security review settings}

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 9c8e4895-48cf-46c7-ba74-e651e8fd448b

📥 Commits

Reviewing files that changed from the base of the PR and between cce8808 and d82f3c1.

📒 Files selected for processing (4)

• src/notifications/channels/discord.js
• src/notifications/channels/teams.js
• src/notifications/channels/text.js
• src/notifications/index.js

---

📝 Walkthrough

Walkthrough

Slack notification formatters now emit valid section blocks containing fields, while Discord, Teams, and text conversions accept fields from both section and legacy fields blocks.

Changes

Slack fields compatibility

Layer / File(s)	Summary
Use section blocks for formatted fields src/notifications/index.js	Stage and task report formatters now place fields on section blocks instead of using the nonstandard fields block type.
Convert fields from section blocks src/notifications/channels/discord.js, src/notifications/channels/teams.js, src/notifications/channels/text.js	Channel converters now process fields attached to both section and fields blocks, preserving compatibility with older payload shapes.

Estimated code review effort: 2 (Simple) | ~10 minutes

Suggested reviewers: richardsongunde

Poem

I’m a rabbit with blocks tucked neat,
Section fields now hop into the right seat.
Discord, Teams, and text all agree,
Old shapes still travel happily.
Ears up for cleaner payloads—whee!

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 40.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title accurately reflects the main fix: replacing an invalid Slack Block Kit fields block with section blocks carrying fields.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix-slack-block-kit-fields-block-type

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[qodo-code-review]

PR Summary by Qodo

Fix Slack Block Kit payloads: move fields onto section blocks

🐞 Bug fix 🕐 20-40 Minutes

AI Description

• Fix Slack payload blocks by using type: "section" for fields.
• Update Teams/Discord/Text converters to read fields from section (legacy-tolerant).

Diagram

graph TD
  Fmt["Slack payload builder"] --> Slack["Slack webhook"]
  Fmt --> DiscordConv["Discord converter"] --> Discord["Discord webhook"]
  Fmt --> TeamsConv["Teams converter"] --> Teams["Teams webhook"]
  Fmt --> TextConv["Text flattener"] --> Text["Plain-text channels"]

Loading

High-Level Assessment

The following are alternative approaches to this PR:

1. Normalize blocks via a shared helper (e.g., `getBlockFields(block)`)

• ➕ Eliminates repeated (section || fields) checks across consumers
• ➕ Centralizes backward-compat handling and makes future schema tweaks safer
• ➖ Slightly more abstraction/indirection for a small codebase
• ➖ Requires touching more files and exporting a helper API

2. Add Block Kit schema validation before sending to Slack

• ➕ Catches invalid payloads early and makes failures explicit
• ➕ Prevents future regressions beyond just the fields issue
• ➖ Adds runtime cost and dependency/maintenance surface
• ➖ Doesn’t address non-Slack consumers unless they also validate

Recommendation: The PR’s approach (fix producer + make consumers tolerant) is the best immediate fix: it restores Slack delivery while preserving compatibility for any persisted/in-flight payloads. If this pattern repeats, consider introducing a small shared normalization helper to avoid duplicating legacy-shape checks.

Files changed (4) +10 / -5

Bug fix (4) +10 / -5

index.jsEmit Block Kit 'section' blocks for 'fields' payloads +4/-2

Emit Block Kit 'section' blocks for 'fields' payloads

• Fixes both Slack payload builders to use 'type: "section"' for blocks that carry 'fields', matching Slack Block Kit’s required shape. Adds clarifying comments explaining why the previous 'fields' block type was invalid.

src/notifications/index.js

discord.jsParse 'fields' from 'section' blocks (legacy-tolerant) +2/-1

Parse 'fields' from 'section' blocks (legacy-tolerant)

• Updates Slack→Discord conversion to treat 'fields' as belonging to 'section' blocks while still accepting legacy blocks with 'type: "fields"'. This preserves embed field extraction for older payloads.

src/notifications/channels/discord.js

teams.jsExtract facts from 'section.fields' (legacy-tolerant) +2/-1

Extract facts from 'section.fields' (legacy-tolerant)

• Adjusts Slack→Teams conversion to read 'block.fields' from 'section' blocks, while continuing to accept the old 'fields' block type. Keeps MessageCard facts output consistent across payload versions.

src/notifications/channels/teams.js

text.jsFlatten 'section.fields' into plain text (legacy-tolerant) +2/-1

Flatten 'section.fields' into plain text (legacy-tolerant)

• Updates plain-text rendering to treat 'fields' as belonging to 'section' blocks, while tolerating the legacy 'fields' block type. Prevents missing details when converting updated Slack payloads into text-only output.

src/notifications/channels/text.js

[qodo-code-review]

Code Review by Qodo

🐞 Bugs (0) 📘 Rule violations (0) 📜 Skill insights (1)

Context used

✅ Compliance rules (platform): 300 rules

✅ Skills: 17 invoked

  code-review-pr

  claude-api

  documentation-writing

  pptx

  docx

  performance-monitoring

  security-compliance

  cso

  plan-eng-review

  design-review

  prompt-engineering

  mcp-builder

  qa-testing

  code-patterns

  xlsx

  security-owasp

  testing-qa

1. Legacy fields branch untested 📜 Skill insight ▣ Testability

Description

A new backward-compatibility branch was added so Slack block parsing accepts both section blocks
with fields and legacy block.type === 'fields', but the existing notification channel tests only
exercise the section path. This leaves the legacy conversion path unverified and risks regressions
for persisted/in-flight payloads shipping unnoticed.

Code

src/notifications/channels/discord.js[R24-26]

+      // Fields ride on a section block; 'fields' is tolerated for older payloads.
+      if ((block.type === 'section' || block.type === 'fields') && block.fields) {
        for (const f of block.fields) {

Relevance

⭐⭐⭐ High

Team often accepts adding regression tests for uncovered branches/edge cases; legacy compatibility
path should be verified.

PR-#399

ⓘ Recommendations generated based on similar findings in past PRs

Evidence

Compliance rules (Rule 1400055 / PR Compliance ID 1399871) require tests to cover both sides of new
or modified conditional branches. The converters now explicitly include a branch for legacy
block.type === 'fields', but the tests construct Slack payloads through formatSlackStageMessage,
which now emits type: 'section' for the fields block; as a result, only the section side of the
condition is exercised and the legacy fields branch is not covered.

src/notifications/channels/discord.js[24-33]
src/notifications/channels/teams.js[27-40]
src/notifications/channels/text.js[26-34]
tests/notifications-channels.test.js[19-42]
src/notifications/index.js[83-96]
src/notifications/channels/text.js[26-28]
Skill: plan-eng-review
Skill: code-review-pr

Agent prompt

The issue below was found during a code review. Follow the provided context and guidance below and implement a solution

## Issue description
Converters now accept both `section` blocks with `fields` and legacy `block.type === 'fields'`, but current tests only exercise the new `section` shape via `formatSlackStageMessage`, leaving the backward-compatibility branch untested.

## Issue Context
This PR explicitly aims to tolerate older persisted/in-flight Slack payloads; without a dedicated test that includes a legacy `{ type: 'fields', fields: [...] }` block, that compatibility guarantee can regress silently. Add a test that feeds a legacy Slack payload using `type: 'fields'` into each converter (e.g., `slackPayloadToText`, `convertSlackToDiscord`, `convertSlackToTeams`) and asserts the expected extracted fields / outputs.

## Fix Focus Areas
- tests/notifications-channels.test.js[19-42]
- src/notifications/channels/discord.js[20-33]
- src/notifications/channels/teams.js[17-40]
- src/notifications/channels/text.js[21-34]

ⓘ Copy this prompt and use it to remediate the issue with your preferred AI generation tools

---

[qodo-code-review]

1. Legacy fields branch untested 📜 Skill insight ▣ Testability

A new backward-compatibility branch was added so Slack block parsing accepts both section blocks
with fields and legacy block.type === 'fields', but the existing notification channel tests only
exercise the section path. This leaves the legacy conversion path unverified and risks regressions
for persisted/in-flight payloads shipping unnoticed.

Agent Prompt

## Issue description
Converters now accept both `section` blocks with `fields` and legacy `block.type === 'fields'`, but current tests only exercise the new `section` shape via `formatSlackStageMessage`, leaving the backward-compatibility branch untested.

## Issue Context
This PR explicitly aims to tolerate older persisted/in-flight Slack payloads; without a dedicated test that includes a legacy `{ type: 'fields', fields: [...] }` block, that compatibility guarantee can regress silently. Add a test that feeds a legacy Slack payload using `type: 'fields'` into each converter (e.g., `slackPayloadToText`, `convertSlackToDiscord`, `convertSlackToTeams`) and asserts the expected extracted fields / outputs.

## Fix Focus Areas
- tests/notifications-channels.test.js[19-42]
- src/notifications/channels/discord.js[20-33]
- src/notifications/channels/teams.js[17-40]
- src/notifications/channels/text.js[21-34]

ⓘ Copy this prompt and use it to remediate the issue with your preferred AI generation tools