Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add britt/agent-skills --skill timeline-planninggit clone --depth 1 https://github.com/britt/agent-skillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/britt/agent-skills/timeline-planning)<a href="https://agentmods.dev/skills/britt/agent-skills/timeline-planning"><img src="https://agentmods.dev/badge/skills/britt/agent-skills/timeline-planning/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/britt/agent-skills/timeline-planning"><img src="https://agentmods.dev/badge/skills/britt/agent-skills/timeline-planning.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00048 | $0.01258 |
| Opus 5 | $0.00024 | $0.00629 |
| Sonnet 5 | $0.00010 | $0.00252 |
| Haiku 4.5 | $0.00005 | $0.00126 |
Grade A, and why
timeline-planning scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 8d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 185 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Timeline Planning Skill
Generate Mermaid Gantt charts that visualize project timelines, task scheduling, phases, and milestones based on GitHub issues and their estimates.
When to Use
Activate this skill when:
- User asks "what would the timeline look like?"
- User says "create a Gantt chart", "show me the project schedule"
- After running the
issue-decompositionskill, to visualize scheduling of the resulting issues - During sprint planning to allocate work
Mermaid Gantt Syntax
Basic Structure
gantt
title Project Timeline
dateFormat YYYY-MM-DD
section Phase 1
Task A :a, 2025-01-15, 2d
Task B :b, after a, 3d
section Phase 2
Task C :c, after b, 2d
Key Elements
title- Chart titledateFormat- How dates are parsedsection- Groups related tasks- Task format:
Name :id, start, duration
Estimate to Duration Conversion
Convert T-shirt size estimates to days:
| Estimate | Duration | Notes |
|---|---|---|
| Small | 1d | Single-day task |
| Medium | 3d | Few days of work |
| Large | 5d | Almost a week |
| XL | 8d | Full week+ |
Adjust based on team velocity, complexity indicators, and buffer for unknowns.
Task States
| Modifier | Meaning | Example |
|---|---|---|
done |
Completed | Task A :done, a, 2025-01-15, 2d |
active |
In progress | Task B :active, b, after a, 3d |
crit |
Critical path | Task C :crit, c, after b, 5d |
milestone |
Milestone | MVP :milestone, m, after c, 0d |
Timeline Patterns
Reusable Gantt patterns (linear project, parallel workstreams, milestones, critical path) are in gantt-patterns.md.
Timeline Generation Process
Step 1: Gather Issues
Prerequisite: fetch the open issues with gh issue list --state open --json number,title,labels,body (requires the gh CLI), or ask the user to paste the issue list.
Gather the following from project issues:
- Issue titles
- Estimates or labels indicating size
- Dependencies or blocking relationships
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 8d ago First seen · 185 lines · 48 tokens per session scan A d2a99fef4946
timeline-planning is a skill published in the GitHub repository britt/agent-skills (5 stars, last pushed 6d ago), licensed MIT. It adds 48 tokens to every session and 1,258 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
Other skills, from other repositories
recipe-create-meet-space
Create a Google Meet meeting space and share the join link.
workthreads
SpecStory Workthreads - a weekly work-thread rollup across a team's repos from SpecStory coding histories (any agent - Claude Code, Codex, Cursor, Gemini, and more). It groups the window's sessions into threads of work per project and labels each new / open / recently closed, so a lead sees what shipped, what is still…
atmos-config
Atmos root configuration: atmos.yaml discovery, precedence, deep merging, basepath, imports, minimal bootstrap, and routing to narrower Atmos skills.
story-readiness
Validate that a story file is implementation-ready. Checks for embedded GDD requirements, ADR references, engine notes, clear acceptance criteria, and no open design questions. Produces READY / NEEDS WORK / BLOCKED verdict with specific gaps. Use when user says 'is this story ready', 'can I start on this story', 'is…
autotask-creator
Rules for automation CRUD from the group-chat commander. The commander does not call mutation tools and does not edit cloud/autotasks files directly. It emits one or more top-level ... containers in its final text; the bus parses and applies them after the turn.
monorepo-management
Master monorepo management with Turborepo, Nx, and pnpm workspaces to build efficient, scalable multi-package repositories with optimized builds and dependency management. Use when setting up monorepos, optimizing builds, or managing shared dependencies.