Yocto Agent Skills

Yocto Agent Skills

Use this root skill as a compatibility router when the full yocto-agent-skills repository is installed as one skill. Prefer the focused skills in skills/ when the host supports skill collections:

• skills/yocto-doc-router for release-aware official documentation routing.
• skills/bitbake-debug for task, log, package, rootfs, and build failure debugging.
• skills/yocto-recipe-review for .bb, .bbappend, .bbclass, dependency, packaging, and override syntax review.
• skills/yocto-layer-review for layer.conf, layer compatibility, priority, dependencies, and bbappend matching.
• skills/yocto-image-rootfs for image recipes, package selection, do_rootfs, pkgdata, and package manager failures.
• skills/yocto-bsp-kernel for machine, BSP, kernel provider, devicetree, U-Boot, and deploy artifacts.
• skills/yocto-security-sbom for license, CVE, SPDX/SBOM, archiver, and compliance workflows.

Keep Yocto Project help grounded in current official documentation, real BitBake metadata, and build logs. Treat Yocto as release-sensitive: syntax, variables, classes, supported hosts, and QA checks can change by release.

Ground Rules

1. Identify the user's Yocto release or branch first. If unknown, inspect LAYERSERIES_COMPAT, conf/layer.conf, poky branch, oe-core branch, or the build output. If still unknown, state the assumption and prefer current docs.
2. Prefer official docs and local metadata over memory. Use references/shared/official-doc-map.md to route questions to the right manual before giving precise guidance.
3. Ask for or inspect the smallest useful evidence: the failing task, the first fatal error, the relevant recipe or bbappend, conf/bblayers.conf, conf/local.conf, and tmp/work/.../temp/log.do_*.
4. Do not present generic Linux fixes as Yocto fixes until you map them to BitBake variables, tasks, classes, packages, or layer configuration.
5. Prefer modern override style (VAR:override, :append, :prepend, :remove) unless the target release requires old syntax.
6. Never recommend deleting tmp/, downloads/, or sstate-cache/ as a first fix. Use targeted clean commands and explain rebuild impact.

Workflow

1. Classify the Request

• Build failure: identify failing task (do_fetch, do_unpack, do_patch, do_configure, do_compile, do_install, do_package, do_package_qa, do_rootfs, do_image, kernel tasks).
• Recipe work: inspect SUMMARY, LICENSE, LIC_FILES_CHKSUM, SRC_URI, SRCREV, S, inherit, DEPENDS, RDEPENDS:${PN}, FILES:${PN}, PACKAGECONFIG, and custom tasks.
• Layer work: inspect conf/layer.conf, BBFILE_COLLECTIONS, BBFILES, BBFILE_PATTERN_*, BBFILE_PRIORITY_*, LAYERSERIES_COMPAT_*, LAYERDEPENDS_*, and bbappend coverage.
• Image work: inspect image recipe, IMAGE_INSTALL, IMAGE_FEATURES, EXTRA_IMAGE_FEATURES, package manager, rootfs logs, and package availability.
• Machine or distro work: inspect MACHINE, DISTRO, MACHINE_FEATURES, DISTRO_FEATURES, tune, kernel provider, bootloader, and BSP layer dependencies.
• Syntax or modernization: inspect override syntax, assignment operators, anonymous Python, variable flags, task ordering, and class inheritance.

2. Gather Evidence

Run or request these commands when available:

bitbake-layers show-layers
bitbake-layers show-recipes <name>
bitbake-layers show-appends
bitbake -e <recipe> | less
bitbake -c listtasks <recipe>
bitbake -c devshell <recipe>
bitbake -c cleansstate <recipe>
bitbake -k <target>
bitbake -g <target>
oe-pkgdata-util list-pkgs
oe-pkgdata-util find-path '*/path/or/file'

For failures, inspect:

tmp/work/<machine-or-arch>/<recipe>/<version>/temp/log.do_<task>
tmp/work/<machine-or-arch>/<recipe>/<version>/temp/run.do_<task>
tmp/work/<machine-or-arch>/<recipe>/<version>/recipe-sysroot*
tmp/deploy/images/<machine>/
tmp/deploy/licenses/
tmp/log/

3. Diagnose by Task

• do_fetch: verify SRC_URI, protocol, branch, SRCREV, checksums, mirrors, credentials, network policy, and DL_DIR.
• do_unpack: verify archive format, S, subdirectory layout, and multi-source unpack paths.
• do_patch: verify patch paths in SRC_URI, strip level, patch order, fuzz, upstream status, and whether apply=yes/no is needed.
• do_configure: verify inherited build class (autotools, cmake, meson, setuptools3, etc.), EXTRA_OECONF, EXTRA_OECMAKE, PACKAGECONFIG, sysroot dependencies, and host contamination.
• do_compile: verify build-time tools in DEPENDS, cross-compile variables, generated headers, parallel build safety, and class-specific compile hooks.
• do_install: verify install destination under ${D}, permissions, ownership, systemd/init files, and installed-vs-shipped packaging coverage.
• do_package / do_package_qa: verify FILES:*, split packages, runtime dependency variables, debug/dev/static package rules, and QA messages.
• do_rootfs: verify package names, runtime providers, IMAGE_INSTALL, package conflicts, license policy, postinstall scripts, and package feed data.
• do_image: verify rootfs completion, IMAGE_FSTYPES, image features, boot artifacts, WIC kickstart files, and deploy output.

4. Review Changes

When reviewing a Yocto patch, produce findings first:

• release compatibility risk
• syntax or override errors
• missing license/source integrity fields
• missing build or runtime dependencies
• layer priority or bbappend risk
• packaging gaps, especially installed files not shipped
• QA suppressions that hide real defects
• host contamination or non-reproducible behavior
• excessive cleans, global config changes, or build directory assumptions

5. Use References

• For official documentation routing, read references/shared/official-doc-map.md.
• For compact domain guidance, task debugging, metadata syntax, variables, QA checks, and review checklists, read references/shared/yocto-field-guide.md.
• For deeper starter references, read references/bitbake/variables-core.md, references/bitbake/classes-core.md, references/yocto/qa-errors.md, and references/yocto/migration.md as needed.
• For image/rootfs, BSP/kernel, security/SBOM, and task catalog work, read references/yocto/image-rootfs.md, references/yocto/bsp-kernel.md, references/yocto/security-sbom.md, and references/bitbake/tasks-reference.md.

Output Style

For troubleshooting, answer with:

1. most likely cause
2. evidence needed or observed
3. exact Yocto/BitBake command or metadata change
4. why it works in Yocto terms
5. official doc section to verify

For code changes, keep edits minimal and release-aware. Show the changed .bb, .bbappend, .conf, or .bbclass snippet and mention the validation command.