Fix timeout-minutes schema documentation: 20 minutes, not 15

[Copilot]

The schema documentation incorrectly stated that timeout-minutes defaults to 15 minutes for agentic workflows. The actual implementation has always used 20 minutes via DefaultAgenticWorkflowTimeoutMinutes constant.

Changes

• Schema documentation (pkg/parser/schemas/main_workflow_schema.json)

  • Updated timeout-minutes field: "15 minutes" → "20 minutes"
  • Updated deprecated timeout_minutes field: "15 minutes" → "20 minutes"

• Test coverage (pkg/workflow/compiler_timeout_default_test.go)

  • Validates 20-minute default applied when timeout-minutes omitted
  • Validates explicit timeout values respected
  • Validates schema documentation matches constant value
  • Prevents future drift between docs and implementation

Example

Workflow without explicit timeout:

---
on: workflow_dispatch
permissions:
  contents: read
engine: copilot
---

Generates step with correct default:

timeout-minutes: 20

The 20-minute default is applied consistently across all engines (Copilot, Claude, Codex) and has been since initial implementation. No code changes required—only documentation correction.

Original prompt

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This section details on the original issue you should resolve

<issue_title>[task] Verify and document timeout-minutes default behavior</issue_title>
<issue_description>## Objective
Investigate the actual timeout-minutes default behavior and update schema documentation to match reality.

Context

The schema claims "Defaults to 15 minutes for agentic workflows" but no code implementation sets this default. This creates misleading documentation. Part of discussion #4010.

Current State

Schema location: pkg/parser/schemas/main_workflow_schema.json

Schema claim: "Defaults to 15 minutes for agentic workflows"

Implementation: Field is extracted but no default value is assigned:

TimeoutMinutes string // extracted from frontmatter, no default set

Investigation Steps

1. Search codebase for timeout-minutes default assignment
2. Check GitHub Actions default timeout (documented as 360 minutes / 6 hours)
3. Test actual workflow behavior when timeout-minutes is omitted
4. Determine intended behavior: 15 minutes or GitHub Actions default

Decision Required

Choose one of these paths:

Option A: Implement 15-minute default

• Add default value assignment in compiler
• Keep schema description as-is
• Files to modify: pkg/workflow/compiler.go or frontmatter extraction logic

Option B: Document actual behavior

• Update schema description to reflect GitHub Actions default (360 minutes)
• No code changes needed
• File to modify: pkg/parser/schemas/main_workflow_schema.json

Files to Investigate

• pkg/parser/schemas/main_workflow_schema.json - Schema documentation
• pkg/workflow/compiler.go - Compiler logic
• pkg/workflow/frontmatter_extraction.go - Field extraction
• Any engine-specific timeout handling

Acceptance Criteria

• Actual timeout-minutes default behavior is verified
• Schema documentation matches implementation
• If default is implemented, tests validate the 15-minute default
• If documentation is updated, it accurately reflects GitHub Actions behavior

Related Information

• GitHub Actions default timeout: 360 minutes (6 hours)
• Current schema claims 15 minutes but this may be unimplemented

AI generated by Plan Command for discussion #4010</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes [task] Verify and document timeout-minutes default behavior #4025

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[Copilot]

Pull Request Overview

This PR corrects documentation in the schema to match the actual implementation: the default timeout for agentic workflows is 20 minutes, not 15 minutes. The default has always been 20 minutes via DefaultAgenticWorkflowTimeoutMinutes constant, but the schema documentation incorrectly stated 15 minutes.

Key changes:

• Updated schema documentation to correctly reflect the 20-minute default
• Added comprehensive test coverage to validate the default timeout behavior and prevent future documentation drift

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
pkg/parser/schemas/main_workflow_schema.json	Updated timeout documentation from "15 minutes" to "20 minutes" for both timeout-minutes and deprecated timeout_minutes fields
pkg/workflow/compiler_timeout_default_test.go	Added new test file with three test functions: validates default timeout applied when omitted, validates explicit timeouts respected, and validates schema documentation matches the constant value

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[Copilot]

This custom intToString helper function is unnecessary. Go's standard library provides strconv.Itoa() for integer-to-string conversion, which is already used elsewhere in the codebase (e.g., pkg/cli/logs.go, pkg/cli/mcp_server.go).

Recommended fix: Remove this function and use strconv.Itoa() on line 89 instead.

[Copilot]

The logic for building expectedTimeoutStr is flawed. Line 87 attempts to convert an integer to a string using string(rune(tt.expectedTimeout+'0')), which works incorrectly for multi-digit numbers. For example, with expectedTimeout=20, this would compute string(rune(68)) = "D", producing "timeout-minutes: D".

While the code on lines 88-90 fixes this for values >= 10 by calling intToString, the initial assignment on line 87 is incorrect and unnecessary.

Recommended fix: Use Go's standard library strconv.Itoa() instead:

import (
    "strconv"
    // ... other imports
)

// In the test:
expectedTimeoutStr := "timeout-minutes: " + strconv.Itoa(tt.expectedTimeout)

This eliminates the need for the custom intToString helper function (lines 121-135) and the conditional check on line 88.