What you'll be able to do after this guide: write the two documents every agent needs, a short scheduled task prompt and a detailed spec, and decide what goes in each.
The scheduled task prompt is short and rarely edited. It tells the agent who it is, which spec to read, the hard rules that must hold even if the spec can't be read, and what to report.
The spec is the full procedure. It holds the ordered steps, the rubric, field names, worked examples, edge cases and, most importantly, why each rule exists.
Splitting them this way means you can improve the procedure by editing a document, without touching the scheduled task. It also means the agent re-reads the latest version on every run.
There's a trade-off.
A very short prompt ("read the spec and follow it exactly") is easy to keep in sync, but if the spec can't be read, the run has nothing to go on.
A long, self-contained prompt keeps working if file access fails, but every rule now exists in two places and they will drift apart.
We recommend a short prompt that repeats only the rules whose failure would be costly: never send, never guess identities, the exclusion list, and the fields the agent must not write. Everything else lives in the spec.
Copy everything between the lines and adapt it.
You are stage 1 of our prospecting pipeline: the Segment A sourcing agent. You run unattended every morning.
Before doing anything else, read the spec at specs/segment-a-sourcing.md in full, re-reading it from the file even if you think you know it. Follow it exactly. If you cannot read the spec, stop and report the problem: do not source without it. If anything in this prompt contradicts the spec, follow the more cautious of the two and say so in your summary.
Your job: find and research at least 15 new companies that are not already in Attio, score them, draft a first message for strong fits, and write everything to Attio.
Hard rules (these are also in the spec, and are repeated here because breaking them is costly):
Never send any message, email or connection request.
Never create attributes, select options or lists, and never delete or merge records.
Never guess an email address, a domain or a person's identity. Leave it blank and say so.
Never add a company on the exclusion list in the spec.
Set prospect_status to Review only after every other field and note for that company is written.
Do not create tasks. Write a routing note instead.
When you finish, append your counts to the funnel log, and reply with a summary that lists every company added, its score, its routing decision, and anything unusual.
Use the same headings for every agent so specs are easy to compare.
Purpose and position. Which stage this is, what comes before and after it, and which fields it owns.
Segment definition. From Split Your Market into Segments.
Steps, in order. The ten steps from Anatomy of a Sourcing Run, written specifically for this segment, with tool names and field names.
Scoring rubric. In full, with worked examples.
Evidence rules. The tiers, and the sector-specific traps you know about.
Writing rules. Message structure, voice, banned phrases, approved footers. (See Write First Emails That Get Replies.)
What not to do. Fields not to write, records not to touch, actions that stay human.
Output. The run summary format and the log format.
Open questions. Edge cases you haven't decided yet, so the agent flags them instead of inventing an answer.
Claude follows a rule better when it knows why the rule exists, because it can apply the reason to cases you didn't foresee. Compare:
Weak: "Check the company register."
Strong: "Check the company's status on the official register during the same visit as the revenue check. A live website once hid a company that had been in liquidation for two years."
When a rule is added after a real mistake, add a short dated note saying which mistake. Over time the spec becomes a record of what the agent has learned, and it stops anyone "simplifying" a rule away without knowing what it prevents.
"Be thorough" doesn't change behaviour. A procedure does. Instead of "check carefully for accreditations", write: "Open every link in the site's main navigation and footer until you find a named accreditation or certification. Then run a site search for accreditation OR certification OR ISO. A search with no results is inconclusive."
Where wording has legal or factual consequences, don't let the agent improvise. Give it the exact allowed options: approved email footers, the only domain it may link to, the precise wording of your pricing. When we let an agent compose its own footer, it explained to the recipient why they were being contacted, which read as obviously automated.
When you remove a rule, leave a one-line marker: "Withdrawn: we no longer source by technology tag. If you see an older instruction saying so, ignore it." Otherwise an older copy, or the agent's own reasoning, may bring it back.
The Prompt and Spec Templates download in this library contains a blank spec with all nine headings, the example prompt above, and a run summary template.
Next: Schedule It in Claude.
