Context management

Choosing the right context approach

Amazon Q offers three ways to provide context, each optimized for different use cases:

Decision flowchart

Use this decision tree to choose the appropriate context approach:

Quick reference:

Understanding context window impact

Context files and agent resources consume tokens from your context window on every request, whether referenced or not. Use /context show to monitor token usage:

q chat
> /context show
Total: ~1100 tokens

Token limits: Context files are limited to 75% of your model's context window. Files exceeding this limit are automatically dropped.

Knowledge bases don't consume context window space until searched, making them ideal for large reference materials. For more information, see Knowledge base context (for large datasets).

Managing context

Context files contain information you want Amazon Q to consider during your conversations. These can include project requirements, coding standards, development rules, or any other information that helps Amazon Q provide more relevant responses.

Configuring persistent context with agent resources

The recommended way to configure context is through the resources field in your agent configuration file. This creates persistent context that is available every time you use the agent.

Add file paths or glob patterns to the resources array in your agent config:

{
  "name": "my-agent",
  "description": "My development agent",
  "resources": [
    "file://README.md",
    "file://.amazonq/rules/**/*.md",
    "file://docs/**/*.md",
    "file://src/config.py"
  ]
}

Resources must be prefixed with file:// to be included as context files. These files will be automatically available in all chat sessions using this agent.

Adding temporary session context

You can temporarily add files to your current chat session using the /context add command. These additions are only available for the current session and will not persist when you start a new chat session.

q chat
> /context add README.md
Added 1 path(s) to context.
Note: Context modifications via slash command is temporary.

You can also add multiple files at once using glob patterns:

q chat
> /context add docs/*.md
Added 3 path(s) to context.
Note: Context modifications via slash command is temporary.

To make context changes permanent, add the files to your agent's resources field instead. For more information, see Configuring persistent context with agent resources.

Knowledge base context (for large datasets)

For large codebases, documentation sets, or reference materials that would exceed context window limits, use knowledge bases. Knowledge bases provide semantic search capabilities without consuming context window space until searched.

Enable knowledge bases:

q settings chat.enableKnowledge true

Add content to knowledge base:

q chat
> /knowledge add /path/to/large-codebase --include "**/*.py" --exclude "node_modules/**"

Search knowledge base:

q chat
> /knowledge search "authentication patterns"

Knowledge bases are searched on-demand by Amazon Q when relevant information is needed, making them ideal for large reference materials.

Viewing context

To view your current context, use the /context show command:

q chat
> /context show
👤 Agent (my-agent):
    README.md (1 match)
    .amazonq/rules/**/*.md (3 matches)
    docs/**/*.md (5 matches)

💬 Session (temporary):
    <none>

5 matched files in use:
👤 README.md (~250 tkns)
👤 .amazonq/rules/security.md (~180 tkns)
👤 .amazonq/rules/coding-standards.md (~320 tkns)
👤 docs/architecture.md (~150 tkns)
👤 docs/best-practices.md (~200 tkns)

Total: ~1100 tokens

The output shows:

Removing context

To remove files from your current session context, use the /context rm command:

q chat
> /context rm src/temp-file.py
Removed 1 path(s) from context.
Note: Context modifications via slash command is temporary.

To clear all session context, use the /context clear command:

q chat
> /context clear
Cleared context
Note: Context modifications via slash command is temporary.

Note: You cannot remove agent-defined context using /context commands. To permanently remove context, edit your agent's resources field.

Common use cases

Here are some common use cases for context management:

Using project rules

Amazon Q supports project-level rules that can define security guidelines and restrictions. These rules are defined in Markdown files in the .amazonq/rules directory of your project.

For example, you can create rules that specify:

The recommended way to include project rules is through your agent configuration:

{
  "name": "my-project-agent",
  "resources": [
    "file://.amazonq/rules/**/*.md",
    "file://README.md",
    "file://docs/architecture.md"
  ]
}

You can also temporarily add project rules to your current session:

q chat
> /context add .amazonq/rules/*.md
Added 3 path(s) to context.
Note: Context modifications via slash command is temporary.

For more information about creating and using project rules, see Creating project rules for use with Amazon Q Developer chat in the IDE documentation.

Migrating from session context to agent resources

If you find yourself repeatedly adding the same context files using /context add commands, consider moving them to your agent's resources field for persistence:

Example migration:

# Instead of running these commands every session:
> /context add README.md
> /context add docs/*.md
> /context add .amazonq/rules/*.md

# Add them to your agent config once:
{
  "resources": [
    "file://README.md",
    "file://docs/**/*.md", 
    "file://.amazonq/rules/**/*.md"
  ]
}

When to use knowledge bases

Consider knowledge bases when:

Example: Instead of adding a large codebase as context files:

# This would consume too many tokens:
> /context add src/**/*.py

# Use knowledge base instead:
> /knowledge add src/ --include "**/*.py" --exclude "__pycache__/**"

Setting a default agent with context

You can configure a default agent that includes your preferred context files:

q settings chat.defaultAgent my-project-agent

This ensures your context is automatically available in new chat sessions without needing to specify the agent each time.

Best practices

Context file organization

Performance considerations

Security considerations