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Context References

Type @ followed by a reference to inject content directly into your message. Hermes expands the reference inline and appends the content under an --- Attached Context --- section.

Supported References

SyntaxDescription
@file:path/to/file.pyInject file contents
@file:path/to/file.py:10-25Inject specific line range (1-indexed, inclusive)
@folder:path/to/dirInject directory tree listing with file metadata
@diffInject git diff (unstaged working tree changes)
@stagedInject git diff --staged (staged changes)
@git:5Inject last N commits with patches (max 10)
@url:https://example.comFetch and inject web page content

Usage Examples

Review @file:src/main.py and suggest improvements

What changed? @diff

Compare @file:old_config.yaml and @file:new_config.yaml

What's in @folder:src/components?

Summarize this article @url:https://arxiv.org/abs/2301.00001

Multiple references work in a single message:

Check @file:main.py, and also @file:test.py.

Trailing punctuation (,, ., ;, !, ?) is automatically stripped from reference values.

CLI Tab Completion

In the interactive CLI, typing @ triggers autocomplete:

  • @ shows all reference types (@diff, @staged, @file:, @folder:, @git:, @url:)
  • @file: and @folder: trigger filesystem path completion with file size metadata
  • Bare @ followed by partial text shows matching files and folders from the current directory

Line Ranges

The @file: reference supports line ranges for precise content injection:

@file:src/main.py:42        # Single line 42
@file:src/main.py:10-25 # Lines 10 through 25 (inclusive)

Lines are 1-indexed. Invalid ranges are silently ignored (full file is returned).

Size Limits

Context references are bounded to prevent overwhelming the model's context window:

ThresholdValueBehavior
Soft limit25% of context lengthWarning appended, expansion proceeds
Hard limit50% of context lengthExpansion refused, original message returned unchanged
Folder entries200 files maxExcess entries replaced with - ...
Git commits10 max@git:N clamped to range [1, 10]

Security

Sensitive Path Blocking

These paths are always blocked from @file: references to prevent credential exposure:

  • SSH keys and config: ~/.ssh/id_rsa, ~/.ssh/id_ed25519, ~/.ssh/authorized_keys, ~/.ssh/config
  • Shell profiles: ~/.bashrc, ~/.zshrc, ~/.profile, ~/.bash_profile, ~/.zprofile
  • Credential files: ~/.netrc, ~/.pgpass, ~/.npmrc, ~/.pypirc
  • Hermes env: $HERMES_HOME/.env

These directories are fully blocked (any file inside):

  • ~/.ssh/, ~/.aws/, ~/.gnupg/, ~/.kube/, $HERMES_HOME/skills/.hub/

Path Traversal Protection

All paths are resolved relative to the working directory. References that resolve outside the allowed workspace root are rejected.

Binary File Detection

Binary files are detected via MIME type and null-byte scanning. Known text extensions (.py, .md, .json, .yaml, .toml, .js, .ts, etc.) bypass MIME-based detection. Binary files are rejected with a warning.

Error Handling

Invalid references produce inline warnings rather than failures:

ConditionBehavior
File not foundWarning: "file not found"
Binary fileWarning: "binary files are not supported"
Folder not foundWarning: "folder not found"
Git command failsWarning with git stderr
URL returns no contentWarning: "no content extracted"
Sensitive pathWarning: "path is a sensitive credential file"
Path outside workspaceWarning: "path is outside the allowed workspace"