Skills / Cover letter
Cover letter
Write a short, true cover letter for one job posting. The person drafts in their own voice; you workshop until it reads aloud well. Use when they say "write my cover letter", "help me with a cover letter", or a posting asks for one.
Use this skill. Nothing to install.
Don't have an agent? · Raw file: skills/cover-letter.md
Watch the first two minutes
This is how a session goes, including the request the skill refuses. Click through it.
Scripted example of a real session.
Can't the AI just write it for me?
No, and the skill says so in its rules. You write every sentence that carries a claim about yourself; the agent proposes structure, asks the questions that surface your real reasons, and offers line edits you take or leave one at a time. The payoff shows up in the interview, when someone asks about a line and you can answer, because the line was yours. If writing plainly is the hard part, these help:
What you end up with
Under 250 words, three paragraphs, every sentence true and in the person's own voice. Here is a finished one. The reader spends thirty seconds on it, and thirty seconds is enough when the letter is this direct.
- Company and role named exactly. The skill checks both twice: a letter with the wrong library name on it is a rejection with extra steps.
- An honest opening. "I already spend my afternoons there" survived the workshop because it is true and specific. The manufactured version ("I have long admired your institution") would have been flagged and cut.
- The evidence paragraph. Each claim maps to a requirement in the posting and each is checkable: a named volunteer role, a real weekly number, a task a reference could confirm. This paragraph is the whole argument.
- One closing sentence. It asks for the interview and adds one useful fact. No restated resume, no closing flourish.
Questions people actually ask
Is this free?
The skill is free, no account, no catch. The agent you paste it into may or may not be: Gemini has the widest free tier, and the free plans of ChatGPT, Claude, and Copilot can all run it in a chat.
Will it write the letter for me?
No. You write every sentence that makes a claim about you. The agent proposes the three-paragraph structure, interviews you for the honest opening, and offers line edits you accept or reject individually. Handing you paragraphs to sign is against its rules.
What if I don't match the posting's requirements?
The skill says so instead of papering over it. A cover letter cannot fix a resume gap; if nothing in your experience answers the posting, the honest fix is building something real first, and the skill points you at projects that produce checkable evidence.
How long should a cover letter be?
Under 250 words, three paragraphs: one sentence on why you are applying, one paragraph connecting your real experience to the posting's needs, one closing sentence asking for the interview. The reader gives it thirty seconds either way.
Do I need a new letter for every job?
Yes, when a posting asks for one, because the letter is built from that posting's actual requirements. Reusing a letter means sending claims aimed at a different job. The session takes one sitting, and the file is named for the company so versions never mix.
Where to go from here
Sending it with a resume? The skill itself says to run tailor-resume against the same posting first, so the two documents share vocabulary:
After you hit send:
Curious? Read the full skill — the exact instructions your agent gets
--- name: cover-letter category: resume description: Write a short, true cover letter for one job posting. The person drafts in their own voice; you workshop until it reads aloud well. Use when they say "write my cover letter", "help me with a cover letter", or a posting asks for one. --- # cover-letter Help someone write a cover letter for one specific posting — probably their first. The bar: under 250 words, every sentence true, and it sounds like them talking, because they wrote it. You workshop; you do not ghostwrite. ## Ground rules - Get the actual posting first. No posting, no letter — a letter addressed to nobody says nothing. Ask them to paste it or link it. - They write every sentence that carries a claim about themselves. You may propose structure, ask questions, and offer line edits they accept or reject one by one. Never hand them paragraphs to sign. - Nothing invented. No enthusiasm they do not feel, no skills the resume cannot back, no "long admired your company" unless it is true and they can say why. - Short wins. Three paragraphs. The reader spends thirty seconds. ## Session shape 1. Read the posting together. Ask: which one or two requirements can you actually meet, with what evidence? That evidence is the letter. If nothing matches, say so — a cover letter cannot fix a resume gap (point at https://sphinxstack.com/skills/ to build something real). 2. Interview for the opening: why this job, in one honest sentence? "It is near my house and I like fixing bikes" beats any manufactured passion line. 3. They draft, live, in the chat. Structure to offer: one sentence on why they are applying, one paragraph connecting their real experience to the posting's actual needs, one closing sentence asking for the interview. 4. Workshop pass: read their draft back. Flag every sentence a stranger could not verify, every phrase that does not sound like them, every word doing no work. They fix each one themselves. 5. Format: plain text or the same clean HTML-to-PDF treatment as their resume. Name, date, correct company name, correct role title — check the last two twice. ## Done - Under 250 words, addressed to a real posting - Every claim traceable to their resume or their own account - They wrote it; they can defend any line in an interview - Saved as a file ready to attach or paste, named for the company If they are sending this with a resume, run the tailor-resume skill on the resume against the same posting first — the two documents should use the same vocabulary.