Default new node content to "Untitled {Type}" for name-as-content core types (project, skill) #1995

Overview

project and skill are Core hardcoded node types whose content field is the node's name, not body text — their NodeBehavior::validate() requires it to be non-empty. Every frontend node-creation path that could reach these types (sidebar "+New", slash commands) always creates instances with content: '', so creation always fails validation. This does not affect primitive/body-content types (text, header, code-block, task, etc.) — empty content is correct and expected for those; this issue is scoped only to types where content is the identity.

Problem Statement

project and skill are Core hardcoded types whose behaviors require non-empty content:

• packages/core/src/behaviors/mod.rs:804 — ProjectNodeBehavior: "content (project name)"
• packages/core/src/behaviors/mod.rs:1909 — SkillNodeBehavior: "Skill name (content) cannot be empty"

Reproduced directly against the daemon:

$ nodespace node create --type skill --content "" --json
Error: ... InvalidArgument, message: "Validation failed: Missing required field: Skill name (content) cannot be empty"

$ nodespace node create --type project --content "" --json
Error: ... InvalidArgument, message: "Validation failed: Missing required field: content (project name)"

Both types have no working creation path as a result:

• Neither is registered in packages/desktop-app/src/lib/plugins/core-plugins.ts, so there is no /project or /skill slash command (confirmed via git log -S — neither was ever added; this is a gap, not a regression/removal).
• The only remaining entry point is the sidebar "+New" button (QueryNodeViewer.handleCreateInstance → createSchemaInstance() in packages/desktop-app/src/lib/services/schema-authoring.ts:24-41), which always creates with content: '' and therefore always fails validation for these two types.

The same content-required pattern exists for three more Core behaviors — no working creation path is confirmed broken for these (they either aren't user-creatable yet or have their own dedicated creation UI), but any future generic creation path for them hits the identical wall unless this fix accounts for them too:

• collection — packages/core/src/behaviors/mod.rs:1655 ("Collection name (content) cannot be empty") — has its own dedicated creation UI already, unaffected in practice
• agent-guidance — packages/core/src/behaviors/mod.rs:1859 ("Agent-guidance title (content) cannot be empty")
• tool — packages/core/src/behaviors/mod.rs:2019 ("Tool display name (content) cannot be empty")

Explicitly not in scope: primitive/body-content types (text, header, code-block, quote-block, ordered-list, task, etc.) correctly create with empty content today — that's the expected "start typing" state, not a bug. This issue must not touch their creation defaults.

Proposed Solution

For the specific set of Core types whose NodeBehavior requires non-empty content (project, skill, and — for consistency, since they share the identical constraint — collection, agent-guidance, tool), default content to "Untitled {Display Name}" at the point(s) where the frontend currently hardcodes content: '' for them:

• createSchemaInstance() (packages/desktop-app/src/lib/services/schema-authoring.ts:24-41) — the sidebar "+New" path; needs to special-case (or look up) this set of types rather than blindly defaulting every type
• Any future core-plugins.ts slash command entries added for project/skill (out of scope to add here, see Non-Goals, but the content-default mechanism should be reusable if/when they're added)

This must be scoped narrowly — by an explicit list, a shared marker, or a lookup against NodeBehavior — so it never applies to primitive body-content types or to titleTemplate-driven custom entities (see Architecture Impact).

Architecture Impact

../nodespace-docs/components/schema-management.md:302 states: "The content field is always empty ('') — never \"Untitled\". Content is not the name." — this line is scoped specifically to the titleTemplate case (custom schema types whose display title is computed from properties via compute_title(), where content is deliberately kept empty as a hidden field, not shown to the user). It sits directly under the doc's "With titleTemplate" behavior section (lines 299-304).

This issue does not reverse that rule and must not apply its default to titleTemplate types (see Non-Goals). No other ADR or architecture doc describes a content-default convention for name-as-content Core types; this issue establishes that convention for the first time, narrowly scoped to that category. No companion nodespace-docs change is required unless the implementer judges the new convention worth documenting alongside the existing titleTemplate section.

Acceptance Criteria

• Sidebar "+New" (createSchemaInstance) creates project and skill instances successfully (previously failed with InvalidArgument)
• project and skill instances created via "+New" default to non-empty, type-identifying content (e.g. "Untitled Project" / "Untitled Skill" — exact wording is an implementation choice)
• Primitive/body-content types (text, header, code-block, task, etc.) are unaffected — verify they still create with empty content, not "Untitled"
• Custom schema types with a titleTemplate are unaffected — their content remains '' per schema-management.md:302
• Regression test: creating a project/skill instance via the sidebar "+New" flow (or the equivalent service-level call) succeeds and round-trips a non-empty content value
• Regression test: creating a primitive type (e.g. text or task) via the same code path still results in empty content
• No new test failures (bun run test:all)
• Code passes bun run quality:fix

Technical Specifications

Reference Files

• packages/desktop-app/src/lib/services/schema-authoring.ts (lines 24-41) — createSchemaInstance(), the sidebar "+New" creation call; currently hardcodes content: '' for every type
• packages/desktop-app/src/lib/components/viewers/query-node-viewer.svelte (line 510-546) — handleCreateInstance(), calls createSchemaInstance() and surfaces createError from a failed create; useful to confirm the error disappears once the fix lands
• packages/core/src/behaviors/mod.rs — validation source of truth: ProjectNodeBehavior::validate (~line 804), SkillNodeBehavior::validate (~line 1909), CollectionNodeBehavior::validate (~line 1655), AgentGuidanceNodeBehavior::validate (~line 1859), ToolNodeBehavior::validate (~line 2019), vs. CustomNodeBehavior::validate (line 2199-2209, explicitly permits empty content) and primitive-type behaviors (no content check)

Implementation Notes

• A display name for the "Untitled {Type}" string can be sourced the same way createPluginFromSchema() derives one: schema.content || humanizeSchemaId(schemaId) (packages/desktop-app/src/lib/plugins/schema-plugin-loader.ts:118).
• Do not touch backend validation (CustomNodeBehavior::validate() or any NodeBehavior impl) — this is purely a frontend default-content fix. The backend behaviors correctly enforce their own rules; the bug is that the frontend never supplies a value that satisfies them for this specific subset of types.
• Prefer an explicit, named list (or a small lookup table) of "name-as-content" types over inferring it from schema shape — there is no existing frontend signal (schema field, isCore flag, etc.) that distinguishes project/skill from task/text; encoding it implicitly (e.g. "core types with no schema fields") would be fragile and likely to silently drift as new Core types are added.

Non-Goals

• Does not implement ai-chat's "Untitled" default or its async LLM title-generation — that is Auto-generate ai-chat conversation titles via idle-gated background LLM task #1698's scope in full.
• Does not change titleTemplate custom-entity behavior — content stays '' for those, per schema-management.md:302.
• Does not change any primitive/body-content type's creation default (text, header, code-block, task, etc.) — empty content is correct for these.
• Does not add a /project or /skill slash command — this issue only fixes the existing "+New" creation path. Adding those slash commands (if desired) is separate, additive scope.

Related Issues

• Auto-generate ai-chat conversation titles via idle-gated background LLM task #1698 (ai-chat's own "Untitled" default + title-generation, explicitly out of scope here)
• Slash command creates custom entity nodes inline #971 (established the titleTemplate "content stays empty as sentinel" precedent this issue must not disturb)