## TL;DR
If github_output is not working, you are almost certainly still using the deprecated set-output command, which GitHub disabled. The fix is to write outputs to the GITHUB_OUTPUT file instead: echo "name=value" >> "$GITHUB_OUTPUT". Check the step for the old syntax first, then verify the output name matches exactly what the consuming step references, including case.

## The query
```text
github_output not working in github actions
```

## Use this when
- A step's outputs are empty in later steps
- You see a deprecation warning about set-output
- Migrating old workflows to the GITHUB_OUTPUT file
- Outputs work locally in act but not on GitHub

## Not for when
- General workflow YAML syntax errors
- Passing files between jobs (use artifacts)
- Secrets not available to steps (different issue)

## Steps

### Step 1: Check for the deprecated set-output command
Search the workflow for set-output. GitHub removed it; any step still using it silently produces no output. This is the cause in the large majority of cases.
Expected output: the old command found and identified, or ruled out.

### Step 2: Switch to the GITHUB_OUTPUT file
Replace the old command with a write to the GITHUB_OUTPUT environment file: echo "my_output=my_value" >> "$GITHUB_OUTPUT". Each output is one line; values with newlines need the heredoc delimiter form.
Expected output: the step writes its outputs to the file GitHub actually reads.

### Step 3: Verify output names match exactly
The consuming step references steps.[id].outputs.[name]. Names are case-sensitive and must match the id: field of the producing step. A typo here produces an empty string with no error, which looks like github_output not working.
Expected output: producer id, output name, and consumer reference all identical.

### Step 4: Check the step actually ran
If the producing step was skipped (an if: condition evaluated false), its outputs are empty. Check the step's conclusion in the run log before debugging the output mechanism.
Expected output: the producing step shows as completed successfully, not skipped.

### Step 5: Test multiline outputs with delimiters
For values containing newlines, use the delimiter syntax (name<<EOF ... EOF) when writing to GITHUB_OUTPUT. A bare echo of a multiline value truncates or corrupts the output.
Expected output: multiline values arrive intact in the consuming step.

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_Yyhu1kOo73cTuubJ7NiIgw