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fix(sdk,plugins): the SDK skill surfaces say a plugin's skills haven't loaded yet, retryable, and carry bundleVersion - #1133
A Skilled OpenAPI server registers its skills from a bundle after it starts. The SDK's own skill surfaces serve those skills too: skills/list, skills/search, skills/load, the SEP-2640 skill:// resources, and the skills line of the initialize instructions. Review found three gaps there.
No bundleVersion.search_skill reports each skill's bundle version, but skills/search and skills/list dropped it, though the registry holds it.
Empty while no bundle is loaded. On a cold start, or after a first pull that failed, these surfaces answered as if the server had no skills. skills/list gave [], skill://index.json an empty index, SKILL.md "not found" or 501, and initialize said nothing about skills. A client kept that answer. The plugin's own tools already said SKILL_BUNDLE_NOT_LOADED.
The signal: SkillCatalogSource.notLoadedReason(). The plugin already provides a SkillCatalogSource under SkillCatalogSourceToken, and initialize already awaits its ready(). This PR adds one optional method to it. It returns why the plugin's skills aren't loaded once ready() has settled, or undefined once they are. The plugin answers from BundleSyncService.notLoadedReason(), the same reason its tools give.
Why this one:
It's the smallest change. There's no new token, provider or registry state, and the SDK never imports the plugin.
The load state stays in one place, the plugin's sync service, and the SDK reads it when it needs it. A registry state that the plugin sets would be a second copy, to keep in step on every apply, failure and push.
Waiting (ready()) stays apart from the answer. A ready() that rejected for "not loaded" would mix the two, and initialize would log every cold start as a failure.
Any plugin that registers skills at runtime can provide it.
What the surfaces answer. Each surface waits for ready() first. On a Worker that wait is what starts the pull, so a client that skips initialize gets the bundle's skills, or the error. While notLoadedReason() gives a reason:
skills/list, skills/search and skill://index.json answer the error. skills/search checks in a new ensureSkillsLoaded stage of the hookable skills:search flow. Lists refuse even on a server that has skills of its own, since a client would keep a partial list as the whole one.
skills/load and skill://<path>/SKILL.md (and the skill's files) answer it only for a skill not found, so the server's own skills still load during a bundle outage.
initialize says, in place of the count or catalog: This server's skills have not loaded yet (<reason>). Ask for them again shortly; the server sends notifications/skills/list_changed once they load. This doesn't apply under injectInstructions: 'off', or 'replace' with server instructions. The reason is collapsed to one line. The skill:// URI hints are left out.
A server without a source answers exactly as before.
The error: SkillBundleNotLoadedError, new in @frontmcp/sdk. It has the code and message the plugin's tools already answered, SKILL_BUNDLE_NOT_LOADED and No skill bundle is loaded: <reason>, with status 503.
As a JSON-RPC error: -32603, with data: { code: 'SKILL_BUNDLE_NOT_LOADED', retryable: true, errorId }.
As a tool result: the same text, and _meta: { code, errorId, timestamp, retryable: true }. The plugin's ensureLoaded now throws this class, so its tools gain _meta.retryable; their text is unchanged.
skills/list had no toSdkMcpError wrapping, so a thrown error lost its code and data. The new check is wrapped.
list_changed once the bundle loads. It's already sent. Each skill the bundle registers emits a registry change, and the notification service sends notifications/skills/list_changed (and notifications/resources/list_changed for the per-skill resources) to every session. The e2e checks that it arrives. Coalescing those into one per kind is separate work.
bundleVersion.skills/list and skills/search are FrontMCP's own methods, and their result types allow extra fields. Their item schemas gain an optional bundleVersion. skills/search takes it from the registry's search result. skills/list reads it with a new optional SkillRegistryInterface.bundleVersionOf(id), from the content the skill was registered with. A skill registered without one keeps its old result shape, with no key. The direct client's SkillSearchResultItem and ListSkillsResult types gain the field. skill://index.json entries follow the agentskills.io discovery schema, so they don't get it.
Scenarios: a saas source that is down at startup, read over a session, over stateless HTTP and through a direct client; then a poll that loads the bundle.
Known limits:
The skills HTTP endpoints (GET /skills, /llm.txt, /llm_full.txt, under skillsConfig.enabled) are unchanged. While no bundle is loaded, /llm.txt still answers 200 with "No skills have been registered on this server".
A bundle that loads with no skills registers none, so no list_changed is sent. A client that got the retryable error then sees an empty list on its retry.
resources/list doesn't refuse; the per-skill SKILL.md resources appear when the bundle loads, with resources/list_changed.
A generated CLI's skills list prints the error and exits 1 while no bundle is loaded, where it printed "No skills found."
User-facing change
What changed:
skills/list and skills/search results carry bundleVersion for a skill registered with one, such as a Skilled OpenAPI bundle skill.
While a plugin's runtime skills haven't loaded, skills/list, skills/search and skill://index.json answer the retryable SKILL_BUNDLE_NOT_LOADED error. So do skills/load and SKILL.md reads, for a skill not found.
While they haven't loaded, initialize says so in its instructions.
The SDK skill surfaces wait for the plugin's skills on every transport, also when the client skips initialize.
New in @frontmcp/sdk: SkillBundleNotLoadedError, SkillCatalogSource.notLoadedReason(), and SkillRegistryInterface.bundleVersionOf().
The Skilled OpenAPI tools' SKILL_BUNDLE_NOT_LOADED result has _meta.retryable: true.
Before → after:
skills/list while the bundle isn't loaded: { skills: [], total: 0 } → JSON-RPC -32603No skill bundle is loaded: <reason>, data: { code: 'SKILL_BUNDLE_NOT_LOADED', retryable: true }.
skill://index.json then: an empty index → the same error.
skill://<id>/SKILL.md then: 501 Skills are not available in this scope → the same error.
skills/load of a bundle skill then: a "not found" warning → the same error.
initialize then: no skills line → This server's skills have not loaded yet (<reason>). Ask for them again shortly; ....
A skills/list item for a bundle skill: { id, name, description, tags } → { id, name, description, tags, bundleVersion }.
frontmcp.dev pages affected (if known):/reference/sdk/skill (skills over MCP, skills/list and skills/search results), /reference/plugins/skilled-openapi (when no bundle loads), /reference/deployment/edge (managed mode before the first bundle), and the errors reference.
skills/list and skills/search answer the retryable error without reading the registry;
skills/load answers it for a skill not found, and still loads a registered one;
once loaded, skills/list and skills/search carry bundleVersion for a bundle skill, and no key for another.
SDK, skill-instructions.helper.spec.ts (6 tests): the not-loaded line under 'compact', 'append' (no skill:// hints) and 'prepend'; none under 'off' or 'replace'; the reason on one line; the count back once loaded.
SDK, skill-catalog-not-loaded.spec.ts (3 tests), a real scope through a direct client:
skills/list, skills/search, skills/load, skill://index.json and SKILL.md answer the error;
once loaded, they list and find the skill with bundleVersion, after notifications/skills/list_changed.
SDK, skill-bundle-not-loaded.error.spec.ts (3 tests): the class, its JSON-RPC answer, and its tool result.
Plugin, bundle-sync.service.spec.ts (2 tests): ensureLoaded throws the SDK class with _meta.retryable; notLoadedReason() before start, after a failure, and once loaded.
Plugin, sdk-skill-surfaces.integration.spec.ts (5 tests), a real server whose saas source is down:
initialize says the skills haven't loaded;
skills/list, skills/search and skill://index.json answer the error, with the code and text search_skill answers;
a direct client gets it too;
after a refresh applies the bundle, skills/list lists its skill with bundleVersion, and list_changed arrived.
demo-e2e-skilled-openapi, sdk-skill-surfaces.e2e.spec.ts (4 tests), a saas source down at startup:
initialize says the skills haven't loaded;
skills/list, skills/search and skill://index.json answer the error over a session;
a stateless 2026-07-28 client, with no initialize, gets the same;
once a poll loads the bundle, they list the skills with bundleVersion 1.0.0, the stateless client sees the same list, and notifications/skills/list_changed arrived.
npx nx test plugin-skilled-openapi: 52 suites, 794 tests, passed.
npx nx test skills: 3 suites, 249 tests, passed.
libs/edge jest: 10 suites, 109 tests, passed.
npx nx test demo-e2e-skilled-openapi: 11 suites, 94 tests, passed.
npx nx test demo-e2e-skills: 10 suites, 193 passed, 2 skipped.
The bundle-size e2e: 12 suites, 63 tests, passed. create() + one tool grew 536 bytes, 1,293,132 → 1,293,668. With WebMcpPlugin it grew 536 bytes, 1,300,364 → 1,300,900. The budgets are set to those sizes. The Vite initial chunk is unchanged at 767,720. SkillBundleNotLoadedError is added to the pinned root exports.
npx nx run <project>:typecheck for sdk, plugin-skilled-openapi and demo-e2e-skilled-openapi, and npx tsc --noEmit -p <lib>/tsconfig.lib.json for the SDK and the plugin: no errors.
Prettier and ESLint on the changed files: clean, with no new warnings.
Summary by CodeRabbit
New Features
Skill listing and search results can now include the originating bundle version.
When a skill bundle is unavailable, skill requests report a retryable error with the load reason instead of appearing empty. Once skills load, clients receive a notification that the skill list changed.
Initialize instructions indicate when skills are still loading or unavailable.
Documentation
Updated guidance to describe bundle availability, retryable errors, and bundle version details.
…aded yet, retryable, and carry bundleVersion
While a Skilled OpenAPI bundle wasn't loaded (a cold start, or a first pull
that failed), initialize, skills/list, skills/search and skill://index.json
answered as if the server had no skills, and clients kept that answer. A
client that skipped initialize (a stateless request, a Worker's first
request) read them before the bundle had even started loading.
The plugin's SkillCatalogSource now has notLoadedReason(). The SDK waits for
the source's ready(), then: initialize says the skills haven't loaded yet;
skills/list, skills/search (a new ensureSkillsLoaded stage of the hookable
skills:search flow) and skill://index.json answer SkillBundleNotLoadedError,
with the plugin tools' code and message and data.retryable; skills/load and
SKILL.md reads answer it for a skill not found. The plugin's tools throw the
same class. A server without a source is unchanged.
skills/list and skills/search results carry bundleVersion for a skill
registered with one; other skills' results are unchanged.
The SDK and Skilled OpenAPI plugin now report unavailable skill bundles through retryable errors. Skill list and search results can include bundle versions. Tests and documentation cover unavailable and loaded bundle states.
Changes: Skill bundle availability
Layer / File(s)
Summary
Catalog readiness and error contract libs/sdk/src/skill/skill-catalog-source.ts, libs/sdk/src/skill/errors/*, libs/sdk/src/errors/mcp.error.ts, plugins/plugin-skilled-openapi/src/sync/bundle-sync.service.ts, plugins/plugin-skilled-openapi/src/skilled-openapi.plugin.ts
The SDK adds SkillBundleNotLoadedError and catalog readiness helpers. The plugin exposes bundle load reasons through its catalog source.
Skill list, search, load, and resource paths check catalog readiness. List and search results include bundleVersion when defined. Instructions show a loading notice when a bundle has not loaded.
Plugin integration and documented behavior plugins/plugin-skilled-openapi/src/__tests__/*, apps/e2e/demo-e2e-skilled-openapi/e2e/*, libs/skills/catalog/*, plugins/plugin-skilled-openapi/README.md, apps/e2e/demo-e2e-bundle-size/e2e/*
Tests cover unavailable and loaded bundle states, including list-changed notifications and bundle versions. Documentation describes the behavior, and the bundle-size budgets increase by 536 bytes for each of two tests.
agentfront/frontmcp#1091: Adds bundle-load failure reporting and bundleVersion to skill search results; this PR extends those contracts across SDK skill surfaces.
agentfront/frontmcp#1081: Documents the use of bundleVersion when clients decide whether to reload skill content.
agentfront/frontmcp#1128: Changes bundle load-state and refresh-failure reporting that this PR uses to report retryable errors when no bundle is available.
Suggested reviewers:alexmercerpo
Merge Risk: Moderate · previous review e6720
A failing catalog status hook can prevent clients from using otherwise registered skills. Guard the hook before merging unless this risk is explicitly accepted.
Pre-merge checks: 4 · 1
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Write docstrings for the functions missing them to satisfy the coverage threshold.
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The title names the main change: SDK skill surfaces now report that a plugin's skills have not loaded yet, with a retryable error, and include bundleVersion. The changeset matches this. The title is l…
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The description follows the repository template. It has 'What and why', 'User-facing change' (with what changed, before/after, pages affected, and catalog entries), and 'Tests' sections. It explains t…
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The title names the main change: SDK skill surfaces now report that a plugin's skills have not loaded yet, with a retryable error, and include bundleVersion. The changeset matches this. The title is long (117 characters) and uses a 'fix(sdk,plugins)' prefix, but it is specific and on topic.
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The description follows the repository template. It has 'What and why', 'User-facing change' (with what changed, before/after, pages affected, and catalog entries), and 'Tests' sections. It explains the motivation, design, error contract, known limits, and validation runs in detail. The 'frontmcp.dev pages affected' and 'Skills catalog entries updated' fields are filled in. The 'Tests' section lists the added tests and the commands run.
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Docstring coverage is 61.54% which is insufficient. The required threshold is 65.00%. Docstring coverage is scoped to functions touched by this diff with cyclomatic complexity of at least 2. Documentation-only edits and deletions within surviving functions are included; unchanged diff context and fully deleted functions are excluded. Analyzed 13 functions across 25 files. (5 skipped: 5 unsupported.)
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Write docstrings for the functions missing them to satisfy the coverage threshold.
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Actionable comments posted: 1
Fix comments: Fix CodeRabbit comments on this PR
Prompt to fix all issues
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Inline comments:
Review comments at @libs/sdk/src/skill/skill-catalog-source.ts:
- Line 102: Update readySkillCatalog to guard the notLoadedReason status hook
just as it guards ready(): if the hook throws, log the error and return the
source without a notLoadedReason, preserving availability of registered skills.
---
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* Cherry-pick: fix(adapters,plugins,edge): an older saas bundle, pulled or pushed, doesn't roll the server back
Cherry-picked from #1119 (merged to release/1.11.x)
Original commit: d88f422
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(sdk,plugins): an @app's Skilled OpenAPI credential resolver reaches execute_action and this.callTool() of an operation
Cherry-picked from #1120 (merged to release/1.11.x)
Original commit: 00a3b00
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(adapters,plugins,edge): a push token replayed to another replica or Worker isolate is refused
Cherry-picked from #1122 (merged to release/1.11.x)
Original commit: 1341026
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(plugins): a skill a skills:filter hook hides can't be run by naming its actions
Cherry-picked from #1123 (merged to release/1.11.x)
Original commit: a081fbf
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(sdk): a plugin listed twice in one plugins list is refused at startup instead of keeping only its last entry
Cherry-picked from #1127 (merged to release/1.11.x)
Original commit: 3dbadd3
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(plugins,edge): a Cron run that doesn't apply its bundle fails, and /readyz says the bundle served is stale
Cherry-picked from #1128 (merged to release/1.11.x)
Original commit: 4938d21
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(sdk): connect() with an authToken connects an anonymous caller again on a server without auth
Cherry-picked from #1129 (merged to release/1.11.x)
Original commit: 3d238da
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(auth,adapters,plugins,edge): operators can tell why a pull or push token was refused, while callers still get the generic answer
Cherry-picked from #1130 (merged to release/1.11.x)
Original commit: 913f4f5
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(sdk,auth,plugins): this.authProviders works: the SDK wires the AuthProviders vault from a new authProvidersVault option
Cherry-picked from #1131 (merged to release/1.11.x)
Original commit: e14c30c
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(sdk,auth): /oauth/connect connects a verified caller who has no vault yet, and asks an anonymous one to sign in
Cherry-picked from #1132 (merged to release/1.11.x)
Original commit: f46a87a
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(sdk,plugins): the SDK skill surfaces say a plugin's skills haven't loaded yet, retryable, and carry bundleVersion
Cherry-picked from #1133 (merged to release/1.11.x)
Original commit: 0d1dc94
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(sdk,auth,cli,plugins): the credentials-required error keeps its connect link out of the message, and asks through URL elicitation where the client supports it
Cherry-picked from #1134 (merged to release/1.11.x)
Original commit: 6d8ea24
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(sdk): a health check registered after startup runs in /readyz, and registerHealthProbe returns a remover
Cherry-picked from #1135 (merged to release/1.11.x)
Original commit: 7f2f48f
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(sdk,plugins): a bundle swap sends one list_changed per list it changed, not one per entry
Cherry-picked from #1136 (merged to release/1.11.x)
Original commit: 0296291
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(adapters,plugins,edge): a restarted server serves its cached bundle in place of an older or refused pull, and doesn't write it back
Cherry-picked from #1137 (merged to release/1.11.x)
Original commit: 358d114
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(sdk,adapters,plugins,edge): a push token with a body_sha256 claim can't carry another bundle
Cherry-picked from #1138 (merged to release/1.11.x)
Original commit: b870325
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(plugins,edge): managed mode takes confirm, and the audit log says whether the user confirmed a call
Cherry-picked from #1139 (merged to release/1.11.x)
Original commit: 588289f
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(cli): the generated CLI says unknown command, prints an MCP error prefix once, and offers load_skill only the run lines it has
Cherry-picked from #1140 (merged to release/1.11.x)
Original commit: 4cfe9a2
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(plugins): load_skill's outputSchema describes a loaded skill once
Cherry-picked from #1141 (merged to release/1.11.x)
Original commit: 470010e
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
* Cherry-pick: fix(sdk,cli): skills/load's default answer sends formattedContent again, as 1.11.0 did; format: 'markdown' is the opt-in for the smaller one
Cherry-picked from #1142 (merged to release/1.11.x)
Original commit: a680fe7
Co-Authored-By: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
---------
Co-authored-by: agentfront[bot] <agentfront[bot]@users.noreply.github.com>
Co-authored-by: frontegg-david <69419539+frontegg-david@users.noreply.github.com>
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Stacks on #1132.
What and why
A Skilled OpenAPI server registers its skills from a bundle after it starts. The SDK's own skill surfaces serve those skills too:
skills/list,skills/search,skills/load, the SEP-2640skill://resources, and the skills line of theinitializeinstructions. Review found three gaps there.bundleVersion.search_skillreports each skill's bundle version, butskills/searchandskills/listdropped it, though the registry holds it.skills/listgave[],skill://index.jsonan empty index,SKILL.md"not found" or501, andinitializesaid nothing about skills. A client kept that answer. The plugin's own tools already saidSKILL_BUNDLE_NOT_LOADED.initialize.initializewaits for the bundle (1.11.0: search_skill's catalog and the server instructions point to skill://index.json, whose SKILL.md has no actions #1067); nothing else did. A stateless request, or a Worker's first request, read the registry before the bundle had even started loading.The signal:
SkillCatalogSource.notLoadedReason(). The plugin already provides aSkillCatalogSourceunderSkillCatalogSourceToken, andinitializealready awaits itsready(). This PR adds one optional method to it. It returns why the plugin's skills aren't loaded onceready()has settled, orundefinedonce they are. The plugin answers fromBundleSyncService.notLoadedReason(), the same reason its tools give.Why this one:
ready()) stays apart from the answer. Aready()that rejected for "not loaded" would mix the two, andinitializewould log every cold start as a failure.What the surfaces answer. Each surface waits for
ready()first. On a Worker that wait is what starts the pull, so a client that skipsinitializegets the bundle's skills, or the error. WhilenotLoadedReason()gives a reason:skills/list,skills/searchandskill://index.jsonanswer the error.skills/searchchecks in a newensureSkillsLoadedstage of the hookableskills:searchflow. Lists refuse even on a server that has skills of its own, since a client would keep a partial list as the whole one.skills/loadandskill://<path>/SKILL.md(and the skill's files) answer it only for a skill not found, so the server's own skills still load during a bundle outage.initializesays, in place of the count or catalog:This server's skills have not loaded yet (<reason>). Ask for them again shortly; the server sends notifications/skills/list_changed once they load.This doesn't apply underinjectInstructions: 'off', or'replace'with server instructions. The reason is collapsed to one line. Theskill://URI hints are left out.A server without a source answers exactly as before.
The error:
SkillBundleNotLoadedError, new in@frontmcp/sdk. It has the code and message the plugin's tools already answered,SKILL_BUNDLE_NOT_LOADEDandNo skill bundle is loaded: <reason>, with status 503.-32603, withdata: { code: 'SKILL_BUNDLE_NOT_LOADED', retryable: true, errorId }._meta: { code, errorId, timestamp, retryable: true }. The plugin'sensureLoadednow throws this class, so its tools gain_meta.retryable; their text is unchanged.skills/listhad notoSdkMcpErrorwrapping, so a thrown error lost its code and data. The new check is wrapped.list_changedonce the bundle loads. It's already sent. Each skill the bundle registers emits a registry change, and the notification service sendsnotifications/skills/list_changed(andnotifications/resources/list_changedfor the per-skill resources) to every session. The e2e checks that it arrives. Coalescing those into one per kind is separate work.bundleVersion.skills/listandskills/searchare FrontMCP's own methods, and their result types allow extra fields. Their item schemas gain an optionalbundleVersion.skills/searchtakes it from the registry's search result.skills/listreads it with a new optionalSkillRegistryInterface.bundleVersionOf(id), from the content the skill was registered with. A skill registered without one keeps its old result shape, with no key. The direct client'sSkillSearchResultItemandListSkillsResulttypes gain the field.skill://index.jsonentries follow the agentskills.io discovery schema, so they don't get it.Scenarios: a saas source that is down at startup, read over a session, over stateless HTTP and through a direct client; then a poll that loads the bundle.
Known limits:
GET /skills,/llm.txt,/llm_full.txt, underskillsConfig.enabled) are unchanged. While no bundle is loaded,/llm.txtstill answers 200 with "No skills have been registered on this server".list_changedis sent. A client that got the retryable error then sees an empty list on its retry.resources/listdoesn't refuse; the per-skillSKILL.mdresources appear when the bundle loads, withresources/list_changed.skills listprints the error and exits 1 while no bundle is loaded, where it printed "No skills found."User-facing change
skills/listandskills/searchresults carrybundleVersionfor a skill registered with one, such as a Skilled OpenAPI bundle skill.skills/list,skills/searchandskill://index.jsonanswer the retryableSKILL_BUNDLE_NOT_LOADEDerror. So doskills/loadandSKILL.mdreads, for a skill not found.initializesays so in its instructions.initialize.@frontmcp/sdk:SkillBundleNotLoadedError,SkillCatalogSource.notLoadedReason(), andSkillRegistryInterface.bundleVersionOf().SKILL_BUNDLE_NOT_LOADEDresult has_meta.retryable: true.skills/listwhile the bundle isn't loaded:{ skills: [], total: 0 }→ JSON-RPC-32603No skill bundle is loaded: <reason>,data: { code: 'SKILL_BUNDLE_NOT_LOADED', retryable: true }.skill://index.jsonthen: an empty index → the same error.skill://<id>/SKILL.mdthen:501 Skills are not available in this scope→ the same error.skills/loadof a bundle skill then: a "not found" warning → the same error.initializethen: no skills line →This server's skills have not loaded yet (<reason>). Ask for them again shortly; ....skills/listitem for a bundle skill:{ id, name, description, tags }→{ id, name, description, tags, bundleVersion }./reference/sdk/skill(skills over MCP,skills/listandskills/searchresults),/reference/plugins/skilled-openapi(when no bundle loads),/reference/deployment/edge(managed mode before the first bundle), and the errors reference.frontmcp-config/references/configure-skills-http.mdfrontmcp-deployment/references/deploy-to-cloudflare-skills-only.mdfrontmcp-development/references/create-skill.mdThe plugin's README is updated too.
Tests
Added:
skills-handlers.spec.ts(6 tests):skills/listandskills/searchanswer the retryable error without reading the registry;skills/loadanswers it for a skill not found, and still loads a registered one;skills/listandskills/searchcarrybundleVersionfor a bundle skill, and no key for another.skill-instructions.helper.spec.ts(6 tests): the not-loaded line under'compact','append'(noskill://hints) and'prepend'; none under'off'or'replace'; the reason on one line; the count back once loaded.skill-catalog-not-loaded.spec.ts(3 tests), a real scope through a direct client:skills/list,skills/search,skills/load,skill://index.jsonandSKILL.mdanswer the error;bundleVersion, afternotifications/skills/list_changed.skill-bundle-not-loaded.error.spec.ts(3 tests): the class, its JSON-RPC answer, and its tool result.bundle-sync.service.spec.ts(2 tests):ensureLoadedthrows the SDK class with_meta.retryable;notLoadedReason()before start, after a failure, and once loaded.sdk-skill-surfaces.integration.spec.ts(5 tests), a real server whose saas source is down:initializesays the skills haven't loaded;skills/list,skills/searchandskill://index.jsonanswer the error, with the code and textsearch_skillanswers;skills/listlists its skill withbundleVersion, andlist_changedarrived.demo-e2e-skilled-openapi,sdk-skill-surfaces.e2e.spec.ts(4 tests), a saas source down at startup:initializesays the skills haven't loaded;skills/list,skills/searchandskill://index.jsonanswer the error over a session;initialize, gets the same;bundleVersion1.0.0, the stateless client sees the same list, andnotifications/skills/list_changedarrived.Run, on the branch merged with #1132:
npx nx run-many -t build -p sdk,adapters,plugin-skilled-openapi,edge,testing: passed.npx nx test sdk: 696 suites, 9699 tests, passed.npx nx test plugin-skilled-openapi: 52 suites, 794 tests, passed.npx nx test skills: 3 suites, 249 tests, passed.libs/edgejest: 10 suites, 109 tests, passed.npx nx test demo-e2e-skilled-openapi: 11 suites, 94 tests, passed.npx nx test demo-e2e-skills: 10 suites, 193 passed, 2 skipped.create()+ one tool grew 536 bytes, 1,293,132 → 1,293,668. With WebMcpPlugin it grew 536 bytes, 1,300,364 → 1,300,900. The budgets are set to those sizes. The Vite initial chunk is unchanged at 767,720.SkillBundleNotLoadedErroris added to the pinned root exports.npx nx run <project>:typecheckfor sdk, plugin-skilled-openapi and demo-e2e-skilled-openapi, andnpx tsc --noEmit -p <lib>/tsconfig.lib.jsonfor the SDK and the plugin: no errors.Summary by CodeRabbit