Build Agent
AnthropicOfficialPublished by Anthropic
- Skill
- Meta (authoring, orchestration, planning, memory)
- Agent tooling
- Apache-2.0
- No issues found
AutoGineer summary
Written by AutoGineer from the skill’s own files, not by the author
Build Agent is a meta-skill designed to capture and formalize an owner's manual workflows into structured, executable agent skills. It guides the process of observing a task, identifying variable versus fixed components, implementing necessary approval gates for safety, and registering the resulting skill for future use or scheduling. By focusing on the owner's specific terminology and validating results against known outcomes, it ensures the generated automation is both trustworthy and practical for team-wide adoption.
What it does
- Observes and extracts task specifications from live conversations or detailed descriptions.
- Distinguishes between fixed process steps and variable inputs like dates or amounts.
- Identifies and inserts approval gates for consequential or ambiguous actions.
- Generates standardized skill documentation including frontmatter and procedural steps.
- Validates the new skill against known-good results before deployment.
- Registers the skill for manual triggering or automated scheduling.
When to use it
- When an owner describes a repetitive task they perform manually.
- When a user asks to automate a routine or build a custom agent.
- When a user expresses a desire for a task to occur on a recurring schedule.
- When you need to convert a one-off manual process into a reliable, reusable workflow.
Advantages
- Reduces manual effort by automating recurring business routines.
- Ensures safety through mandatory approval gates for sensitive actions.
- Maintains user trust by using the owner's specific terminology.
- Enables team-wide collaboration by sharing formalized, tested skills.
- Prevents over-automation by balancing manual oversight with execution.
Usage examples
- “I do this every Monday, can you build me an agent to handle my commission reconciliation?”
- The agent will analyze your current process, identify the fixed steps and judgment points, and draft a reusable skill for commission reconciliation.
- “I want this to happen every week without me, can you turn this into a workflow?”
- The agent will capture the steps of your current task, build a formal skill, and set up a recurring schedule for it to run automatically.
Install
Download the skill as a ZIP:
https://mp-staging.autogineer.com/agent-skills/anthropics/build-agent/downloadUnzip it into the cross-client skills folder of your project:
mkdir -p .agents/skills && unzip build-agent.zip -d .agents/skills
Documentation by Anthropic
Build Agent
Turn something the owner does every week into something they ask for by name.
This is what keeps the plugin from having to ship every industry's workflow. No catalog can cover a septic contractor's permit routine or an insurance agency's carrier commission reconciliation. Those owners can build them.
Step 1 — Watch it happen, or hear it described
Two starting points, and the first is much better.
Best: they just did it in this conversation. If the owner has walked through the task with you — pulled the files, made the decisions, corrected you twice — that transcript is the specification. Extract it rather than re-interviewing them. The corrections they made are the most valuable part, because they encode judgment the owner would never have thought to state.
Otherwise: they describe it. Ask them to walk through the last time they did it, concretely. Real specifics beat an abstract description every time — "last Tuesday I pulled the carrier file, matched it against what we'd booked, and chased six discrepancies" tells you more than "I reconcile commissions."
Read reference/capture.md for how to get a complete picture without an interrogation.
Step 2 — Separate what varies from what stays fixed
This is the whole craft of the step. A skill that hardcodes last Tuesday's specifics only works on last Tuesday.
For each part of the task, decide:
Fixed — the sequence, the sources, the output format, the rules
Varies — dates, names, amounts, which file, which customer
Judgment — the parts where the owner decides, which become approval gates
The corrections the owner made while walking through it usually mark the judgment points. When someone says "no, not that one — we skip anything under USD 50," that is a rule. When they say "hmm, depends," that is an approval gate.
Step 3 — Find the approval gates
Every step that sends, spends, publishes, or deletes needs a gate. So does every step where the owner hesitated.
Do not gate everything — a skill that asks permission nine times is worse than doing it by hand. Gate the consequential and the ambiguous, and let the rest run.
Read reference/skill_authoring.md for where gates belong and how to phrase them.
Step 4 — Write it
Produce a real skill in the same shape as everything else in this plugin: a SKILL.md with frontmatter and numbered steps, plus a reference/ folder if the detail warrants it.
Requirements it must meet, same as every shipped skill:
Name and folder match, lowercase with hyphens
Description says what it does and when to trigger, in third person
A real fallback for when a connector is missing
Approval gates on anything consequential
Never invents a number; missing data is reported as missing
Write it in the owner's terms, not in generic business language. If they call it "the carrier file," the skill says carrier file. A skill full of unfamiliar vocabulary is one they will not trust to run unattended.
Step 5 — Test it on a real case, before they rely on it
Run the new skill against a case the owner already knows the answer to — ideally the exact one they walked through. Show the output next to what they got by hand.
This is the step that determines whether the skill gets used. An owner who has seen it reproduce a known-good result will schedule it. One who hasn't will run it manually and check it every time, which saves nothing.
If it doesn't match, fix the skill and run it again. Do not ask the owner to accept a near-miss.
Step 6 — Register and set the cadence
Add it to smb-router so plain-English requests reach it, and record the trigger phrases the owner actually uses.
If it is a recurring task, offer to schedule it. Scheduling is what converts "a skill I could run" into "something that happens without me," which is the outcome they wanted.
Step 7 — Share it, with approval
Offer to share with the team. Say what sharing means: who gets it, what data it can reach, and what it can do unattended.
Be specific about the risk when a skill sends, spends, or writes. A skill that emails customers, running for someone who did not build it and does not know its assumptions, is a real hazard. Recommend draft-only for shared skills that send anything.
What not to do
Do not re-interview about a task they just walked through. The transcript is the spec.
Do not hardcode the example. Names, dates, and amounts vary; the sequence does not.
Do not gate every step. Nine approvals is worse than doing it by hand.
Do not skip the test run. An untested skill gets checked manually forever, which saves nothing.
Do not write it in generic business language. Their words, or they won't trust it.
Do not build something that sends or spends without approval gates. Ever, regardless of what the owner asks for.
After the build
The owner now has a named skill they can trigger or schedule. If the new skill hit a tool that isn't connected, "connect to my ERP" (build-connector) is the natural next step — it turns the missing system into a working source. Also nearby: "brief me" to fold the new output into the daily picture, and "Monday brief" if the skill should feed the weekly one. Offer at most three, and skip any offer the owner already declined this session.
Reference files
reference/capture.md— getting a complete picture of the task without an interrogationreference/skill_authoring.md— the structure, frontmatter, and where approval gates belongreference/gotchas.md— the failure modes that produce a skill nobody uses
Files
- ATTRIBUTION.mdAdded by AutoGineer903 B
- LICENSELicence file added by AutoGineer11.3 KiB
- SKILL.md6.4 KiB
- reference/capture.md4.4 KiB
- reference/gotchas.md5.0 KiB
- reference/skill_authoring.md5.7 KiB
SKILL.md
Build Agent
Turn something the owner does every week into something they ask for by name.
This is what keeps the plugin from having to ship every industry's workflow. No catalog can cover a septic contractor's permit routine or an insurance agency's carrier commission reconciliation. Those owners can build them.
Step 1 — Watch it happen, or hear it described
Two starting points, and the first is much better.
Best: they just did it in this conversation. If the owner has walked through the task with you — pulled the files, made the decisions, corrected you twice — that transcript is the specification. Extract it rather than re-interviewing them. The corrections they made are the most valuable part, because they encode judgment the owner would never have thought to state.
Otherwise: they describe it. Ask them to walk through the last time they did it, concretely. Real specifics beat an abstract description every time — "last Tuesday I pulled the carrier file, matched it against what we'd booked, and chased six discrepancies" tells you more than "I reconcile commissions."
Read reference/capture.md for how to get a complete picture without an interrogation.
Step 2 — Separate what varies from what stays fixed
This is the whole craft of the step. A skill that hardcodes last Tuesday's specifics only works on last Tuesday.
For each part of the task, decide:
Fixed — the sequence, the sources, the output format, the rules
Varies — dates, names, amounts, which file, which customer
Judgment — the parts where the owner decides, which become approval gates
The corrections the owner made while walking through it usually mark the judgment points. When someone says "no, not that one — we skip anything under USD 50," that is a rule. When they say "hmm, depends," that is an approval gate.
Step 3 — Find the approval gates
Every step that sends, spends, publishes, or deletes needs a gate. So does every step where the owner hesitated.
Do not gate everything — a skill that asks permission nine times is worse than doing it by hand. Gate the consequential and the ambiguous, and let the rest run.
Read reference/skill_authoring.md for where gates belong and how to phrase them.
Step 4 — Write it
Produce a real skill in the same shape as everything else in this plugin: a SKILL.md with frontmatter and numbered steps, plus a reference/ folder if the detail warrants it.
Requirements it must meet, same as every shipped skill:
Name and folder match, lowercase with hyphens
Description says what it does and when to trigger, in third person
A real fallback for when a connector is missing
Approval gates on anything consequential
Never invents a number; missing data is reported as missing
Write it in the owner's terms, not in generic business language. If they call it "the carrier file," the skill says carrier file. A skill full of unfamiliar vocabulary is one they will not trust to run unattended.
Step 5 — Test it on a real case, before they rely on it
Run the new skill against a case the owner already knows the answer to — ideally the exact one they walked through. Show the output next to what they got by hand.
This is the step that determines whether the skill gets used. An owner who has seen it reproduce a known-good result will schedule it. One who hasn't will run it manually and check it every time, which saves nothing.
If it doesn't match, fix the skill and run it again. Do not ask the owner to accept a near-miss.
Step 6 — Register and set the cadence
Add it to smb-router so plain-English requests reach it, and record the trigger phrases the owner actually uses.
If it is a recurring task, offer to schedule it. Scheduling is what converts "a skill I could run" into "something that happens without me," which is the outcome they wanted.
Step 7 — Share it, with approval
Offer to share with the team. Say what sharing means: who gets it, what data it can reach, and what it can do unattended.
Be specific about the risk when a skill sends, spends, or writes. A skill that emails customers, running for someone who did not build it and does not know its assumptions, is a real hazard. Recommend draft-only for shared skills that send anything.
What not to do
Do not re-interview about a task they just walked through. The transcript is the spec.
Do not hardcode the example. Names, dates, and amounts vary; the sequence does not.
Do not gate every step. Nine approvals is worse than doing it by hand.
Do not skip the test run. An untested skill gets checked manually forever, which saves nothing.
Do not write it in generic business language. Their words, or they won't trust it.
Do not build something that sends or spends without approval gates. Ever, regardless of what the owner asks for.
After the build
The owner now has a named skill they can trigger or schedule. If the new skill hit a tool that isn't connected, "connect to my ERP" (build-connector) is the natural next step — it turns the missing system into a working source. Also nearby: "brief me" to fold the new output into the daily picture, and "Monday brief" if the skill should feed the weekly one. Offer at most three, and skip any offer the owner already declined this session.
Reference files
reference/capture.md— getting a complete picture of the task without an interrogationreference/skill_authoring.md— the structure, frontmatter, and where approval gates belongreference/gotchas.md— the failure modes that produce a skill nobody uses
Requirements and compatibility
Written for: Claude Code, Claude apps
Works with: Claude Code, Claude apps, OpenAI Codex, GitHub Copilot, Cursor, Gemini CLI, Kiro, OpenCode, Goose, Amp, Roo Code, JetBrains Junie, Factory Droid, Devin (ex-Windsurf), Mistral Vibe, OpenHands, Letta
“Works with” means the tool reads the open Agent Skills format; a skill written for one tool may use features others lack.
Needs: Declares allowed tools
Security
No issues found by our static scan· No issues found
A static scan is not a guarantee. Skills are third-party content: review a skill before you let an agent use it.
Attribution and licence
- Published by
- Anthropic
- Publisher
- Anthropic (Official)
- Source
- anthropics/knowledge-work-plugins · small-business/skills/build-agent · commit e050c2e
- Licence
- Apache License 2.0 (redistribution allowed)
- LICENSE (added by AutoGineer from LICENSE)
- ATTRIBUTION.md (written by AutoGineer)
- Synced
AutoGineer is not affiliated with or endorsed by Anthropic.
Download ZIP
The ZIP holds the skill’s files, its licence files and an ATTRIBUTION.md. Download build-agent.zip