# Concepts

A query describes behavior you want to find. ev-grep reads each selected file and asks Jev whether it matches.

The same query accompanies each file; files do not share context.

## File context

An assessment receives the path and complete text of one file. A retry loop may be visible in `retry.ts`, while
`client.ts` delegates to a transport defined elsewhere. The latter may need a person or review agent to investigate.

ev-grep does not fetch dependencies, build an index, or compare revisions. Searching files from a PR examines their
current contents, not whether the diff introduced a problem.

## Part of a file

A path such as `src/users.py:20-56` narrows an assessment to those lines. Jev still receives the whole file as
context and judges what the selected lines do, including what same-file helpers they call do. Code elsewhere in the
file that the lines don't use does not make them match. A range of changed lines asks what that code does now; it
still does not show whether the change introduced it. [Use with other tools](./pipelines.md) shows how to get ranges
from `git diff` or ast-grep.

## Decisions

`match` retains a file. `no_match` omits it from terminal output. `uncertain` retains it for further review.
All three appear in [JSON output](./output.md). A failed request is an error, not a decision.

Model results can be wrong. A search helps choose what to read; it does not prove that code follows a rule.

## Requests

File discovery and glob filtering happen locally. Each selected text file then becomes one provider request, with up
to four requests in flight by default (`--jobs` changes the limit). Use `--dry-run` to inspect file selection without a key or API calls.

```text diagram
   selected files             up to 4 requests
  ┌──────────────┐       ┏━━━━━━━━━━━━━━━━━━━━━━┓
  │ file A       │──────▶┃ query + A  →  Jev    ┃
  │ file B       │──────▶┃ query + B  →  Jev    ┃
  │ file C       │──────▶┃ query + C  →  Jev    ┃
  │ file D       │──────▶┃ query + D  →  Jev    ┃
  │ file E, …    │       ┗━━━━━━━━━━┳━━━━━━━━━━━┛
  └──────────────┘                  │
       waiting                      ▼
                          results as they finish
```

When a request finishes, the next file takes its place. JSONL includes every result; terminal output lists matches
and uncertain files.

Requests use your provider account and may incur charges. See [Providers](./providers.md) for configuration,
[Request limits](./limits.md) for bounds, and [Benchmarks](./benchmarks.md) for measured timings.