Changelog

Dated record of knowledge-sync changes and notable manual updates. Newest first. Each entry cites the source it came from.

• Maintainer mode syncs edit this file directly (then you commit & publish).
• Consumer mode syncs write to ${COPILOT_PLUGIN_DATA}/CHANGELOG.md instead, leaving this read-only.

Format:

## YYYY-MM-DD
- [source-id] what changed -> what was edited. (source: URL) [auto|review]

2026-10-02 (b)

• [cli-plugin-reference] Agent Plugins 1.0 is a separate, closed manifest format, not an add-on. The previous build-cli-plugin note ("$schema is additive on top of normal loading") was wrong. A spec manifest must be a root plugin.json, allows only metadata fields (skills/agents/hooks/mcpServers are ignored), loads skills only from skills/ and MCP only from a root mcp.json with the matching spec $schema, and puts Copilot-only agents/hooks under com.github.copilot/. The CLI accepts spec 1.0.0 and 1.1.0 and rejects unsupported versions → build-cli-plugin now defaults to Agent Plugins for every plugin (agents/hooks/commands go under com.github.copilot/; legacy only for custom component paths or clients without spec support), documents both layouts, adds templates/agent-plugin.json, and uses copilot --plugin-dir as the no-install test loop. This plugin itself moved to the spec layout (plugin.json at the root, hook at com.github.copilot/hooks/hooks.json). (source: https://docs.github.com/en/copilot/reference/copilot-cli-reference/cli-plugin-reference) [review → applied]
• [cowork-plugin-development] Verified by running atk 1.1.18 on 2026-10-02: atk import openplugin reads a root Agent Plugins plugin.json directly (the doc's .plugin/ move isn't needed). Imported manifests copy the plugin version, and M365 validation rejects versions starting with 0. atk validate --manifest-file works without sign-in, and atk package requires m365agents.yml. Windows PowerShell 5.1 Compress-Archive writes backslash entry names → updated build-cowork/SKILL.md (convert section, Step 5, checklist) and templates/plugin-package/README.md. (source: https://learn.microsoft.com/en-us/microsoft-365/copilot/cowork/cowork-plugin-development) [auto]

2026-10-02

• [cowork-plugin-development] Resolves the 2026-08-14 review item. Doc now leads with the Agents Toolkit CLI: atk import openplugin (CLI ≥1.1.12; Claude/Cursor/.plugin → atk project, devPreview manifest, placeholder referenceId, UUID v5 id), atk export openplugin, atk package; PowerShell conversion script is now "legacy". mcpToolDescription is optional ("Cowork discovers tools dynamically and doesn't use this file"). ApiKey auth not yet supported in Cowork; omitting authorization (implicit DCR) is Cowork-only; OAuth registrations should target "Any Microsoft 365 Organization". New: MCP annotations drive confirmation (unannotated = destructive), contentEncoding: base64 file inputs, copilot-cowork client identity, dev-tunnel local testing, tenant publish path now Manage apps → Upload custom app → Add agent → updated build-cowork/SKILL.md and templates/plugin-package/README.md. Templates kept on v1.29: verified the published v1.28 schema still requires mcpToolDescription (v1.29/v1.30 don't), so the doc's v1.28 sample is not safe for dynamic discovery. (source: https://learn.microsoft.com/en-us/microsoft-365/copilot/cowork/cowork-plugin-development) [review → applied]
• [m365-agent-connectors] New auth types DynamicClientRegistration (explicit, with referenceId; server must return client_id + client_secret) and AzureKeyVault (schema v1.29+); OAuth redirect URI https://teams.microsoft.com/api/platform/v1.0/oAuthRedirect → auth table in build-cowork, links; source added to sources.json. (source: https://learn.microsoft.com/en-us/microsoftteams/platform/m365-apps/agent-connectors) [auto]
• [federated-connectors] Added custom federated connectors (admin-created; read-only tools; OAuth requires client ID + secret) and contrasted them with package agentConnectors[] in build-cowork → new links section; source added to sources.json; lesson recorded. (source: https://learn.microsoft.com/en-us/microsoft-365/copilot/connectors/set-up-custom-federated-connectors) [auto]
• [m365-overview-plugins, m365-plugin-manifest, m365-declarative-agent-manifest] Pages updated 2026-09-30; no new version paths (plugin 2.5, DA 1.9/1.10, app manifest v1.31 all 404) → last_known_updated only. [auto]
• [cowork-plugins, cowork-customize, cowork-elicitation-forms] Pages updated 2026-09-14/15; no impact found on templates → last_known_updated only. [auto]
• [cli-plugin-reference, cli-plugins-creating, cli-add-skills, vscode-agent-plugins] First content-hash baseline recorded (no prior hash, so change can't be determined this run). [auto]

2026-08-14

• [cli-plugin-reference] Doc URL moved under /reference/copilot-cli-reference/ → updated sources.json and links.md. Verified this repo's .github/plugin/ layout is still third in the documented manifest search order. New $schema field opts a plugin into the Agent Plugins (Open Plugin Spec) 1.0 format → added to build-cli-plugin manifest table. (source: https://docs.github.com/en/copilot/reference/copilot-cli-reference/cli-plugin-reference) [auto]
• [vscode-agent-plugins] Agent Plugins 1.0 GA (2026-08-12): VS Code now auto-discovers plugins installed by the Copilot CLI from ~/.copilot/installed-plugins/, installs from marketplaces via the chat.plugins.marketplaces setting, and honors workspace recommendations in .github/copilot/settings.json (extraKnownMarketplaces, enabledPlugins) → updated build-cli-plugin Step 5, surface-comparison.md, links.md; source added to sources.json. (source: https://code.visualstudio.com/docs/agent-customization/agent-plugins) [auto]
• [cli-add-skills] Documented skill discovery order (.github/skills > .agents/skills > .claude/skills > parent dirs > ~/.copilot/skills > ~/.agents/skills > plugins > COPILOT_SKILLS_DIRS), /skills session commands, the copilot skill subcommand, and install --skill --scope user|project → source added to sources.json, /skills reload noted in the build-cli-plugin iteration loop. (source: https://docs.github.com/en/copilot/how-tos/copilot-cli/customize-copilot/add-skills) [auto]
• [m365-declarative-agent-manifest] Declarative agent manifest 1.7 → 1.8 (adds EmailActions + MeetingActions capabilities; EmbeddedKnowledge.files now required) → updated links.md, surface-comparison.md, and the sources.json url. Plugin manifest 2.4 verified still current — no 2.5. (source: https://learn.microsoft.com/en-us/microsoft-365/copilot/extensibility/declarative-agent-manifest-1.8) [auto]
• [cowork-plugin-development] Needs review, not applied: the Cowork build doc's sample now pins Unified App Manifest v1.28 (strict) and states mcpToolDescription is required on remoteMcpServer — in tension with the v1.29 dynamic-discovery path this repo ships and has uploaded successfully (lessons.md 2026-06-25). Unified manifest v1.30 (Aug 2026) is latest GA but only adds Outlook add-in fields. Left the v1.29 templates and customer-architect manifest unchanged; verify against a real Cowork upload before any change. Also new in the doc: workspace file inputs for connectors (contentEncoding: base64, ≤8 files, 150 MiB each), 20-skills/10-connectors package limits, MCP annotations driving confirmation prompts (unannotated tools treated as destructive). (source: https://learn.microsoft.com/en-us/microsoft-365/copilot/cowork/cowork-plugin-development) [review]
• [cowork-plugins, cowork-customize] Cowork user-facing flows updated: self-service plugin upload with automatic Claude-plugin package conversion, plugin sharing/re-share, skill upload accepting .md/.zip/.skill (1 MB per .md, 10 MB compressed / 50 MB uncompressed / 100 files per archive) → sources.json notes refreshed. (source: https://learn.microsoft.com/en-us/microsoft-365/copilot/cowork/cowork-customize) [auto]

2026-06-25

• Initial release of copilot-extension-builder. Baseline knowledge captured from Microsoft Learn and GitHub Copilot docs; seven sources seeded in references/sources.json with last_checked 2026-06-25 and check_interval_days 14.
• [github-cli] Verified during build that direct path installs are deprecated by the CLI → README and build-cli-plugin now lead with plugin@marketplace. (source: cli-plugin-reference) [auto]
• [github-cli] Verified that a local marketplace add requires an absolute path (a relative ./ is read as a GitHub repo). Documented in README and build-cli-plugin. (source: cli-plugin-reference) [auto]