---
title: "Review a letter"
method: POST
path: "/v1/tools/letterlens"
---

# Review a letter

`POST /v1/tools/letterlens`

## Request

- Base URL: `https://api.counselorai.app`
- URL: `https://api.counselorai.app/v1/tools/letterlens`
- Auth: HTTP bearer

Analyze a finished recommendation letter and return specific fixes: what is vague, what is asserted without evidence, what reads as generated. Read-only and far cheaper than drafting. Use it to critique a draft, not to rewrite one, and use revision to apply the fixes.

## Headers

- `Idempotency-Key` string
- `X-Max-Credits` integer

## Request body

- object
  - `letterText` string, required: The letter to review, as plain text.
  - `purpose` 'rec_college' | 'rec_scholarship' | 'rec_transfer' | 'rec_professional' | 'rec_employment' | 'rec_program' | 'undergraduate' | 'graduate' | 'scholarship' | 'transfer' | 'internship' | 'other': What the letter is for. A scholarship letter is read differently from a transfer letter.
  - `focus` string: A specific thing to look hardest at, if there is one.

## Response `200`

Tool output

- object
  - `request_id` string
  - `tool` string
  - `output` object
    - `text` string, required: The generated output.
    - `meta` object: Pipeline metadata (pipeline, verify status, fix pass).
    - `verification` object: Whether a model verify pass checked this text, and its verdict.
      - `checked` boolean
      - `method` string, nullable
      - `status` 'PASS' | 'FAIL' | 'null', nullable
      - `score` integer, nullable
      - `fix_applied` boolean, nullable
    - `grounding` object: What the generation was anchored to. fact_sheet is the exact ground truth the verify pass checked dollar figures, names, and dates against; null for tools without a fact-grounded verify pass.
      - `fact_sheet` string, nullable
      - `fields_reflected_in_prompt` string[]
      - `fields_mapped_or_transformed` string[]
      - `fields_not_reflected` string[]
    - `input_fidelity` string: 'strict': this lane never truncates silently; an over-limit input is rejected with a validation error, so the output was built on exactly what was sent.
  - `billing` object
    - `status` 'settled' | 'pending'
    - `credits_charged` integer, nullable
    - `credits_remaining` integer, nullable

## Other responses

- `402`: Insufficient credits or approved spending limit exceeded. Inspect error.code.
- `429`: Rate limited. Retry after the Retry-After header.

---

[API](https://skmtc.dev/counselorai/apis/counselorai-api.md) · [All operations](https://skmtc.dev/counselorai/apis/counselorai-api/llms.txt) · [OpenAPI document](https://skmtc.dev/counselorai/apis/counselorai-api/revisions/1d93eed35463?raw)