GitHub Actions reusable workflow "with:" input type mismatch
A reusable workflow declares each input with a type (string, boolean, number). Passing a value of the wrong type via with - most often a quoted string where a boolean is expected - fails validation.
What this error means
The caller fails to start the reusable workflow, reporting that a with input does not match the declared type.
##[error]Invalid value. Input 'deploy' expects type 'boolean' but was provided 'true' as a string.Diagnose it: print the context before you change anything
Most workflow-expression bugs are not syntax errors, they are an expression reading something that is empty. GitHub resolves a missing property to an empty string instead of failing the run, so a wrong reference looks like a logic bug rather than a mistake. Dump the contexts first and you will usually see the answer immediately.
- name: Dump contexts
run: |
echo '--- github ---' ; echo '${{ toJSON(github) }}'
echo '--- needs ---' ; echo '${{ toJSON(needs) }}'
echo '--- steps ---' ; echo '${{ toJSON(steps) }}'
echo '--- matrix ---' ; echo '${{ toJSON(matrix) }}'
echo '--- inputs ---' ; echo '${{ toJSON(inputs) }}'Check the context is allowed where you used it
Contexts are not available everywhere. The same expression can be valid in a step if and invalid in a job if, which is why an expression that works in one workflow fails when moved.
| Where you wrote it | Contexts available there |
|---|---|
run-name | github, inputs, vars |
concurrency | github, inputs, vars |
Top-level env | github, secrets, inputs, vars |
jobs.<id>.if | github, needs, vars, inputs |
jobs.<id>.steps.if | github, needs, strategy, matrix, job, runner, env, vars, steps, inputs |
jobs.<id>.outputs | Full access, including secrets |
Reusable workflow outputs | github, jobs, vars, inputs |
Common causes
Boolean passed as a quoted string
A with value like "true" (quoted) is a string, but the input is typed boolean, so validation rejects it.
Expression result type differs from declared type
An interpolated value resolves to a string while the input expects number or boolean.
How to fix it
Match the value type to the input type
- Pass booleans unquoted and numbers as numeric literals.
- When using an expression, ensure it yields the declared type (wrap with fromJSON or a comparison if needed).
- Re-run.
jobs:
call:
uses: ./.github/workflows/deploy.yml
with:
deploy: true # boolean, unquoted
replicas: 3 # numberCatch it before it reaches CI
Every failure in this cluster is statically detectable. actionlint parses workflow expressions, checks context availability against the same rules above, and validates needs references, so these bugs never need to cost you a run.
# one-off
docker run --rm -v "$(pwd):/repo" --workdir /repo rhysd/actionlint:latest -color
# as a job, before anything expensive runs
- uses: actions/checkout@v4
- run: |
bash <(curl -s https://raw.githubusercontent.com/rhysd/actionlint/main/scripts/download-actionlint.bash)
./actionlint -colorHow to prevent it
- Pass with values in the declared input type; do not quote booleans or numbers.
- Declare explicit input types in workflow_call so mismatches fail early.