Borrowing it
Nothing to install: this file belongs to Artesiana/agent2. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/Artesiana/agent2/main/.agents/skills/adding-capabilities/SKILL.mdgit clone --depth 1 https://github.com/Artesiana/agent2Wrote 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/artesiana/agent2/adding-capabilities)<a href="https://agentmods.dev/skills/artesiana/agent2/adding-capabilities"><img src="https://agentmods.dev/badge/skills/artesiana/agent2/adding-capabilities/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/artesiana/agent2/adding-capabilities"><img src="https://agentmods.dev/badge/skills/artesiana/agent2/adding-capabilities.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 | $0.00039 | $0.01182 |
| Opus 5.5 | $0.00016 | $0.00473 |
| Sonnet 5.5 | $0.00008 | $0.00236 |
| Haiku 4.5 | $0.00004 | $0.00118 |
Grade A, and why
adding-capabilities 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 2mo 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 — 182 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Adding Capabilities to Agents
Overview
Agent2 capabilities are opt-in. Start with a simple agent (schema + tools + prompt), then add capabilities as your use case requires them.
When to Activate
- User says "add resume", "add approval", "add knowledge", "add provider policy"
- Agent needs multi-turn conversations
- Agent needs human-in-the-loop before executing side effects
- Agent needs cost-optimized provider routing
- Agent needs per-request tool filtering
Capability Quick Reference
| Capability | When You Need It | What It Adds |
|---|---|---|
| Pause/Resume | Multi-turn workflows, clarification loops | message_history serialization |
| Approval Workflow | Human must approve before side effects | pending_actions + execute endpoint |
| Provider Policy | Cost control, prompt cache optimization | provider_order in config |
| Tool Scoping | Per-tenant or per-request tool filtering | Tool policy in before_run() |
| Knowledge Search | Agent needs domain documents | R2R + Knowledge MCP via toolsets= |
Pause/Resume
Add when: Agent needs to ask a question and wait for a human to answer before continuing.
1. Accept history in before_run
def before_run(input_data: dict) -> dict:
if input_data.get("message_history"):
input_data["_instructions"] = (
"Continue the conversation. Read the human's response and proceed."
)
return input_data
2. Persist history in after_run
The framework auto-serializes _message_history into the response. Your host product stores it wherever it wants (Redis, Postgres, Convex, etc.) and sends it back on the next call.
3. Advertise in config
capabilities:
- resume
Approval Workflow
Add when: Agent proposes side effects (send email, update records, make payments) that need human sign-off.
1. Return pending_actions from agent output or mock_result
def mock_result(input_data: dict) -> dict:
return {
"status": "needs_approval",
"pending_actions": [
{
"action": "send_email",
"params": {"to": "[email protected]", "body": "..."},
"description": "Send follow-up email to the client.",
}
],
}
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.
- 2mo ago First seen · 182 lines · 39 tokens per session scan A 0c13676bd32c
adding-capabilities is a skill published in the GitHub repository Artesiana/agent2 (37 stars, last pushed 6mo ago), licensed MIT. It adds 39 tokens to every session and 1,182 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-08-30.
adding-capabilities compared with skills from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| adding-capabilitiesArtesiana/agent2 | Skill | 37 | 6mo ago | MIT | A | 39 | Claude Code, Codex |
| frontend-featurevstorm-co/full-stack-ai-agent-template | Skill | 2.0k | 7d ago | MIT | A | 64 | Claude Code |
| alembic-migrationvstorm-co/full-stack-ai-agent-template | Skill | 2.0k | 7d ago | MIT | A | 56 | Claude Code |
| billing-stripevstorm-co/full-stack-ai-agent-template | Skill | 2.0k | 7d ago | MIT | A | 56 | Claude Code |
| Agent Managementsseshachala/conductai | Skill | 32 | 2d ago | Apache-2.0 | A | 14 | Claude Code |
| video_action_recognitionfdueblab/Micro-Agent | Skill | 100 | 1mo ago | MIT | A | 0 | Claude Code, Codex |
| trade_compliancefdueblab/Micro-Agent | Skill | 100 | 1mo ago | MIT | A | 0 | Claude Code, Codex |