# August 2026 source capability notes

> Review the six merged source capabilities, their product boundaries, migration requirements, and availability before planning an upgrade.

Six capability pull requests are integrated in Nibleaf source on `main`. They
form one coherent control plane for search, usage, add-ons, themes,
integrations, and agent access. This is source availability, not deployment
evidence: the committed self-host manifest still points to v0.1.2, and no Cloud
or self-host deployment is performed by these documentation changes.

## Integrated source baseline

| Capability | Pull request | Main commit | What changed |
| --- | --- | --- | --- |
| Project add-ons | #103 | `7fd56e22810fca0b073ec6a6d81cfa2c8ec5e874` | Durable add-on state, entitlement-aware availability, consent controls, reader actions, publish checks, and audit history. |
| Documentation themes | #104 | `4afdce5ad3ad3010ef33238015baaa36ee770871` | Harbor, Manuscript, and Signal render distinct responsive structures with safe template import/export and portable Git repositories. |
| Usage metering | #105 | `7210ca4481192da9f2ba2a0df36cc1a08caef7f0` | Provider-neutral exact quantities, advisory entitlements, reconciliation, export, deletion, and degraded states across Postgres and optional ClickHouse. |
| Search configuration | #106 | `24b47d096562c8f222880ca5275a6c623e0c2594` | Project settings, privacy-safe index diagnostics, bounded reindex controls, and reader configuration for the hybrid search foundation. |
| Integrations engine | #107 | `767b2fa6ef0a63c4c8498696038ecc35419e6d25` | Project-owned provider connections, encrypted credentials, revisions, idempotency, verification, confirmation, audit, and key rotation. |
| MCP control plane | #108 | `9fb787ef438ecee0b65da9c785ab42dd3f2bdc1c` | Authenticated project-bound HTTP MCP with least-privilege read adapters, audit, expiration, host checks, and bounded rate limiting. |

## Search and grounded answers

The search domain supports tenant-, deployment-, language-, version-, and
reader-authorization-scoped retrieval. Project settings expose result count,
language/version filters, and optional grounded answers. Diagnostics show
health, counts, stable issue codes, and bounded identifiers; they never return
document content or vectors.

Hybrid operation is not a universal quality claim. Keep `SEARCH_RUNTIME=shadow`
until real acceptance queries and provider evidence support a cutover. The
immediate retrieval rollback remains `legacy`. Unsupported grounded answers are
withheld rather than invented. See [search and AI operations](/self-hosting/search-ai).

## Usage and entitlement truth

Usage facts use provider-neutral meters and exact integer quantities. Postgres
owns plans, assignments, entitlements, checkpoints, and bounded low-volume
receipts; optional ClickHouse stores high-volume facts and rollups. Coverage can
be complete, partial, or unavailable. Missing history is never presented as
zero, and the feature does not enable billing or payments.

Limits remain advisory in this source capability set. Export waits for pending
or late usage to reconcile, and privacy deletion covers both stores and search
erasure boundaries. See [usage metering](/self-hosting/usage-metering).

## Add-ons and consent

Project add-ons group reader engagement, privacy, and publishing helpers behind
durable state and explicit entitlements. Feedback records a bounded sentiment
event; edit and issue links require safe URL templates; consent gates optional
analytics; local publish checks validate internal links and an explicitly
preview-quality grammar linter. See [project add-ons](/use-nibleaf/add-ons).

## Portable documentation themes

Harbor, Manuscript, and Signal now own different reader structures rather than
acting as color presets. All three use the same Markdown/MDX contract, semantic
tokens, localization, search, metadata, and immutable publication boundary.
Theme templates are deterministic, schema-validated JSON without executable
CSS or JavaScript. Standalone Git exports separate platform, shared-content, and
customer-owned files. See [documentation themes](/use-nibleaf/themes).

## Integrations and MCP

The integration engine separates external provider connections from add-ons and
usage. It encrypts configurable credentials with a dedicated key, redacts
responses and audits, uses revisions and idempotency, and requires explicit
confirmation for destructive deletion. A provider listed in the catalog is not
proof that its runtime or credentials are available.

MCP exposes project-bound read adapters for capabilities, published content,
search configuration and diagnostics, aggregate usage, entitlements, add-ons,
theme catalogs/templates, integration summaries, and bounded operational
metadata. It cannot publish, reindex, export usage, accept provider credentials,
or mutate the new domains. Theme-import preview validates without writing. See
[integrations](/reference/integrations-engine) and [MCP](/self-hosting/mcp).

## Upgrade boundary

The Postgres migrations must run in timestamp order, with integrations before
MCP because integrations owns `ApiKey.expiresAt`. Optional ClickHouse migrations
and reconciliation have their own gate. Read the
[combined migration and rollback guide](/self-hosting/combined-release-migration)
before selecting a source revision or future image.

Do not replace the v0.1.2 installer, compose digest, or container reference with
these commits. A future published artifact needs its own build, security and
migration checks, exact digest, release notes, and signed-out runtime validation.