Console: create-time "prompt-for-value" picker for bundle ${input} templates (mcp servers + secrets)

[mabry1985]

Summary

Build one console "prompt-for-value at create time" picker that collects ${input} values when a new agent is created from a bundle/archetype, and writes the resolved config. It's the shared front-end for two already-designed backend seams (ADR 0083 D5):

• Bundle/archetype seam: first-class mcp: field for seeding MCP servers #2011 — bundle mcp: field (shipped backend, PR feat(bundles): seedable MCP servers via a bundle mcp: field (ADR 0083 D5, #2011) #2039): MCP server templates carry ${key} placeholders + an inputs list. Today they resolve only from the seed-time environment; an unresolved required input seeds the server enabled: false (visible-but-inert). The interactive prompt is deferred to this picker.
• Archetype/bundle seam: env + secrets seeding #2014 — bundle secrets:/env seeding (deferred pending this): archetypes want to ask the operator for API keys at create time instead of a post-install settings hunt. This is fundamentally a prompt-for-value flow — it has no useful backend-only form (pre-creating empty secret fields adds nothing; auto-resolving secrets from host env widens blast radius, against ADR 0080's inherit_env non-leak posture). So it waits on this picker.

Both use the same input contract already established by config/mcp-catalog.json:

inputs: [ { key, label, placeholder?, required?, secret?, default? } ]

and the same ${key} placeholder syntax (graph/mcp_config._PLACEHOLDER / the console's McpCatalogDialog.fillTemplate). Building it once, for both, is the right sequencing.

What to build

1. Detect when a picked archetype's bundle declares inputs (via mcp: templates and/or a secrets: field). The archetype-preview path (GET /api/archetypes/{id}/preview, ADR 0083 / feat(archetypes): archetype preview — see skills/plugins/SOUL before picking #2016) already peeks the bundle — surface its inputs there.
2. Prompt in the new-agent flow (NewAgentPanel / SetupWizard) — reuse McpCatalogDialog's inputs→fillTemplate→submit UI: SecretInput for secret: true, required-but-empty gate, etc.
3. Resolve + write at create:
   • mcp: fill the ${input} templates and union into the workspace mcp.servers (the #2011 seeder path — collected values replace the current env-only resolution / seeded-disabled fallback).
   • secrets: write collected values to the member's <ws>/config/secrets.yaml via graph/config_io.save_secrets (nested {section:{key:val}}, 0600, atomic, merge-not-clobber). This is the missing half of Archetype/bundle seam: env + secrets seeding #2014 — the backend secrets: field + _apply_bundle_secrets seeder land here alongside the picker (they're inert without it).

Security posture (secrets)

• Values are collected from the operator, never auto-copied from the host os.environ (that would persist a host-scoped credential into a new instance's secrets.yaml, a larger blast radius than the fleet's env-inheritance — flagged against ADR 0080). Any host-env resolution stays explicit opt-in, off by default.
• secret: true inputs never echo back (redacted from /api/config like model.api_key); the create request carrying them must not be logged.

Acceptance

• A bundle whose mcp: templates carry required ${input}s prompts the operator at create; the resulting MCP servers are seeded enabled with the supplied values (no more seeded-disabled fallback when the picker is used).
• A bundle secrets: field prompts the operator at create; values land in the member's secrets.yaml (0600), redacted from /api/config, never from host env.
• Backend secrets: field + _apply_bundle_secrets seeder implemented (the Archetype/bundle seam: env + secrets seeding #2014 backend, gated behind this picker).
• Consumers unblocked: close/advance Archetype/bundle seam: env + secrets seeding #2014; drop Bundle/archetype seam: first-class mcp: field for seeding MCP servers #2011's env-only/seeded-disabled interim note.

Refs: ADR 0083 D5, #2011 (PR #2039), #2014, #2016 (archetype preview), ADR 0080 (secrets posture), config/mcp-catalog.json (input contract).

[mabry1985]

Shipped across three slices, all merged: #2122 (peek_bundle/lock enrichment — preview now exposes bundle mcp inputs + secrets declarations), #2125 (POST /api/fleet accepts operator inputs + secrets; operator values seed MCP servers ENABLED; _apply_bundle_secrets writes via save_secrets — the #2014 backend), #2127 (the create-time picker in NewAgentPanel + preview dialog enrichment, fillTemplate extracted to lib). Known limitation tracked separately: flat input keys collide across servers sharing an input name — #2128. Host-path seeding: #2118.