Read tables back as Markdown instead of smearing their cells

internal/tui/workspace/views/detail.go

@@ -757,9 +757,9 @@ func (v *Detail) startCommentEdit() tea.Cmd {
 		return nil
 	}
 	c := v.data.comments[v.focusedComment]
-	// Fail closed on table-bearing content (see startEditBody).
-	if richtext.HasTableHTML(c.content) {
-		return workspace.SetStatus("This comment contains a table — edit it on Basecamp web", true)
+	// Fail closed on complex tables (see startEditBody).
+	if richtext.HasComplexTableHTML(c.content) {
+		return workspace.SetStatus("This comment contains a table too complex to edit as Markdown — edit it on Basecamp web", true)
 	}
 	v.editingComment = true
 	v.commentEditComposer = widget.NewComposer(v.styles,
@@ -1078,10 +1078,12 @@ func (v *Detail) startEditBody() tea.Cmd {
 	if v.data == nil {
 		return nil
 	}
-	// Fail closed on table-bearing content: HTMLToMarkdown has no table handling,
-	// so entering edit mode and resubmitting would strip the table. Block the edit.
-	if richtext.HasTableHTML(v.data.content) {
-		return workspace.SetStatus("This message contains a table — edit it on Basecamp web", true)
+	// Fail closed on complex tables — shapes a GFM pipe table can't
+	// represent (see richtext.HasComplexTableHTML): HTMLToMarkdown flattens
+	// them, so an edit-and-resubmit would lose structure. Simple grids
+	// round-trip and stay editable.
+	if richtext.HasComplexTableHTML(v.data.content) {
+		return workspace.SetStatus("This message contains a table too complex to edit as Markdown — edit it on Basecamp web", true)
 	}
 	v.editingBody = true
 	v.bodyEditComposer = widget.NewComposer(v.styles,

internal/tui/workspace/views/detail_test.go

@@ -573,12 +573,18 @@ func TestDetail_CommentEdit_Ignored_WhenNoFocus(t *testing.T) {
 	assert.False(t, v.editingComment)
 }
 
-const tableHTML = "<figure><table><thead><tr><th>Foo</th></tr></thead>" +
+// A simple grid round-trips through HTMLToMarkdown and stays editable; a
+// merged-cell grid cannot be represented as a GFM pipe table, so its edits
+// fail closed.
+const simpleTableHTML = "<figure><table><thead><tr><th>Foo</th></tr></thead>" +
 	"<tbody><tr><td>Baz</td></tr></tbody></table></figure>"
 
-func TestDetail_EditBody_BlockedForTable(t *testing.T) {
+const complexTableHTML = "<figure><table><thead><tr><th>Foo</th><th>Bar</th></tr></thead>" +
+	"<tbody><tr><td colspan=\"2\">Baz</td></tr></tbody></table></figure>"
+
+func TestDetail_EditBody_BlockedForComplexTable(t *testing.T) {
 	v := testDetailWithSession("Message", false)
-	v.data.content = tableHTML
+	v.data.content = complexTableHTML
 
 	cmd := v.startEditBody()
 	assert.False(t, v.editingBody, "must not enter edit mode on table content")
@@ -601,10 +607,35 @@ func TestDetail_EditBody_EntersForNonTable(t *testing.T) {
 	assert.NotNil(t, cmd)
 }
 
-func TestDetail_CommentEdit_BlockedForTable(t *testing.T) {
+func TestDetail_EditBody_EntersForSimpleTable(t *testing.T) {
+	v := testDetailWithSession("Message", false)
+	v.data.content = simpleTableHTML
+
+	cmd := v.startEditBody()
+	assert.True(t, v.editingBody, "should enter edit mode on simple-table content")
+	require.NotNil(t, v.bodyEditComposer, "composer should be built")
+	assert.NotNil(t, cmd)
+	assert.Equal(t, "| Foo |\n| --- |\n| Baz |", v.bodyEditComposer.Value(),
+		"composer should hold the table as Markdown")
+}
+
+func TestDetail_CommentEdit_EntersForSimpleTable(t *testing.T) {
+	v := detailWithComments()
+	v.focusedComment = 0
+	v.data.comments[0].content = simpleTableHTML
+
+	cmd := v.startCommentEdit()
+	assert.True(t, v.editingComment, "should enter edit mode on simple-table content")
+	require.NotNil(t, v.commentEditComposer, "composer should be built")
+	assert.NotNil(t, cmd)
+	assert.Equal(t, "| Foo |\n| --- |\n| Baz |", v.commentEditComposer.Value(),
+		"composer should hold the table as Markdown")
+}
+
+func TestDetail_CommentEdit_BlockedForComplexTable(t *testing.T) {
 	v := detailWithComments()
 	v.focusedComment = 0
-	v.data.comments[0].content = tableHTML
+	v.data.comments[0].content = complexTableHTML
 
 	cmd := v.startCommentEdit()
 	assert.False(t, v.editingComment, "must not enter edit mode on table content")

internal/tui/workspace/views/todos.go

@@ -1042,10 +1042,12 @@ func (v *Todos) startEditDescription() tea.Cmd {
 		}
 	}
 
-	// Fail closed on table-bearing content: HTMLToMarkdown has no table handling,
-	// so entering edit mode and resubmitting would strip the table. Block the edit.
-	if richtext.HasTableHTML(description) {
-		return workspace.SetStatus("This to-do description contains a table — edit it on Basecamp web", true)
+	// Fail closed on complex tables — shapes a GFM pipe table can't
+	// represent (see richtext.HasComplexTableHTML): HTMLToMarkdown flattens
+	// them, so an edit-and-resubmit would lose structure. Simple grids
+	// round-trip and stay editable.
+	if richtext.HasComplexTableHTML(description) {
+		return workspace.SetStatus("This to-do description contains a table too complex to edit as Markdown — edit it on Basecamp web", true)
 	}
 
 	v.editingDesc = true

internal/tui/workspace/views/todos_test.go

@@ -942,20 +942,23 @@ func TestTodos_BoostTarget_IncludesAccountID(t *testing.T) {
 	assert.Equal(t, int64(42), picker.Target.ProjectID)
 }
 
-// --- Edit description: table fail-closed guard ---
+// --- Edit description: complex-table fail-closed guard ---
 
-const todoTableHTML = "<figure><table><thead><tr><th>Foo</th></tr></thead>" +
+const todoSimpleTableHTML = "<figure><table><thead><tr><th>Foo</th></tr></thead>" +
 	"<tbody><tr><td>Baz</td></tr></tbody></table></figure>"
 
-func TestTodos_EditDescription_BlockedForTable(t *testing.T) {
+const todoComplexTableHTML = "<figure><table><thead><tr><th>Foo</th><th>Bar</th></tr></thead>" +
+	"<tbody><tr><td colspan=\"2\">Baz</td></tr></tbody></table></figure>"
+
+func TestTodos_EditDescription_BlockedForComplexTable(t *testing.T) {
 	v := testTodosViewWithTodos()
 
 	todos := sampleTodos()
-	todos[0].Description = todoTableHTML
+	todos[0].Description = todoComplexTableHTML
 	v.session.Hub().Todos(42, 10).Set(todos)
 
 	cmd := v.startEditDescription()
-	assert.False(t, v.editingDesc, "must not enter edit mode on table content")
+	assert.False(t, v.editingDesc, "must not enter edit mode on complex-table content")
 
 	require.NotNil(t, cmd, "should return a status command")
 	status, ok := cmd().(workspace.StatusMsg)
@@ -977,6 +980,21 @@ func TestTodos_EditDescription_EntersForNonTable(t *testing.T) {
 	assert.NotNil(t, cmd)
 }
 
+func TestTodos_EditDescription_EntersForSimpleTable(t *testing.T) {
+	v := testTodosViewWithTodos()
+	v.descComposer = widget.NewComposer(v.styles, widget.WithMode(widget.ComposerRich))
+
+	todos := sampleTodos()
+	todos[0].Description = todoSimpleTableHTML
+	v.session.Hub().Todos(42, 10).Set(todos)
+
+	cmd := v.startEditDescription()
+	assert.True(t, v.editingDesc, "should enter edit mode on simple-table content")
+	assert.NotNil(t, cmd)
+	assert.Equal(t, "| Foo |\n| --- |\n| Baz |", v.descComposer.Value(),
+		"composer should hold the table as Markdown, line structure intact")
+}
+
 // newTextInputWithValue creates a textinput with a preset value for testing.
 func newTextInputWithValue(val string) textinput.Model {
 	ti := textinput.New()

skills/basecamp/SKILL.md

@@ -97,12 +97,17 @@ Full CLI coverage: 155 endpoints across todos, cards, messages, files, schedule,
    - **`@Name` / `@First.Last`** — fuzzy name resolution (may be ambiguous)
    For todos, documents, and cards, content is sent as-is — use plain text or HTML directly.
 
-   **Table boundary:** GFM tables render in message/comment bodies, but the TUI
-   in-place editors **refuse to open** table-bearing content (edit it on Basecamp
-   web, or replace the whole field via `messages update` / `comments update` /
-   `todos update --description`, which take fresh content and are unaffected), and
-   human-readable CLI/TUI **display** of such content may lose table structure —
-   both pending server-side Markdown support (BC3 #11986).
+   **Table boundary:** GFM tables round-trip: they render in message/comment
+   bodies, display converts them back to pipe tables, and the TUI in-place
+   editors open simple grids for editing. Only **complex** tables — merged
+   cells (colspan/rowspan), captions, extra header rows, nested tables,
+   attachments/images or block content inside cells, multi-paragraph or
+   multi-line cells, or a table inside a blockquote or list — refuse to open,
+   since a GFM pipe table can't represent those shapes (edit them on Basecamp
+   web, or replace the
+   whole field via `messages update` / `comments update` / `todos update
+   --description`, which take fresh content and are unaffected). Complex
+   tables still **display** best-effort, flattened to a plain grid.
 
    **Multiline / non-ASCII content:** do not rely on bash ANSI-C quoting (`$'...\n...'`) — it is a bash/zsh extension. Under a POSIX `/bin/sh` (dash, busybox-ash, common in sandboxes) the `$` is passed through literally and posts a stray leading `$`, and `\n` stays a literal backslash-n. Pipe the content via stdin instead, using `-` as the content argument:
    ```bash