copy edits for agent harness (#1162)

## Overview
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## Type of change

**Type:** [Replace with: New documentation page / Update existing
documentation / Fix typo/bug/link/formatting / Remove outdated content /
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## Checklist
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- [x] I have read the [contributing guidelines](README.md)
- [x] I have tested my changes locally using `docs dev`
- [x] All code examples have been tested and work correctly
- [ ] I have used **root relative** paths for internal links
- [x] I have updated navigation in `src/docs.json` if needed
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## Additional notes
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Author: lnhsingh

src/docs.json

@@ -268,13 +268,13 @@
                     "group": "Get started",
                     "pages": [
                       "oss/python/deepagents/quickstart",
-                      "oss/python/deepagents/harness",
                       "oss/python/deepagents/customization"
                     ]
                   },
                   {
                     "group": "Core capabilities",
                     "pages": [
+                      "oss/python/deepagents/harness",
                       "oss/python/deepagents/backends",
                       "oss/python/deepagents/subagents",
                       "oss/python/deepagents/human-in-the-loop",

src/oss/deepagents/harness.mdx

@@ -1,40 +1,40 @@
 ---
-title: Harness Capabilities
-description: Description of what capabilities come in the deepagents Agent Harness
+title: Agent harness capabilities
+sidebarTitle: Agent harness
 ---
 
-We think of `deepagents` as an "agent harness".
-It is the same core tool calling loop as other agent frameworks, but with built-in tools and capabilities.
-Here we list out the components that make up this agent harness
+We think of `deepagents` as an "agent harness". It is the same core tool calling loop as other agent frameworks, but with built-in tools and capabilities.
 
-## Filesystem Access
+This page lists out the components that make up the agent harness.
 
-Provides 6 tools for file system operations, making files first-class citizens in the agent's environment.
+## File system access
 
-**Tools provided:**
-- `ls` - List files in a directory with metadata (size, modified time)
-- `read_file` - Read file contents with line numbers, supports offset/limit for large files
-- `write_file` - Create new files
-- `edit_file` - Perform exact string replacements in files (with global replace mode)
-- `glob` - Find files matching patterns (e.g., `**/*.py`)
-- `grep` - Search file contents with multiple output modes (files only, content with context, or counts)
+The harness provides six tools for file system operations, making files first-class citizens in the agent's environment:
+
+| Tool | Description |
+|---|---|
+| `ls` | List files in a directory with metadata (size, modified time) |
+| `read_file` | Read file contents with line numbers, supports offset/limit for large files |
+| `write_file` | Create new files |
+| `edit_file` | Perform exact string replacements in files (with global replace mode) |
+| `glob` | Find files matching patterns (e.g., `**/*.py`) |
+| `grep` | Search file contents with multiple output modes (files only, content with context, or counts) |
 
----
 
-## Large Tool Result Eviction
+## Large tool result eviction
 
-Automatically dumps large tool results to the filesystem when they exceed a token threshold, preventing context window saturation.
+The harness automatically dumps large tool results to the file system when they exceed a token threshold, preventing context window saturation.
 
 **How it works:**
+
 - Monitors tool call results for size (default threshold: 20,000 tokens)
 - When exceeded, writes the result to a file instead
 - Replaces the tool result with a concise reference to the file
 - Agent can later read the file if needed
 
----
-## Pluggable Storage Backends
+## Pluggable storage backends
 
-Abstracts filesystem operations behind a protocol, allowing different storage strategies for different use cases.
+The harness abstracts file system operations behind a protocol, allowing different storage strategies for different use cases.
 
 **Available backends:**
 
@@ -59,11 +59,10 @@ Abstracts filesystem operations behind a protocol, allowing different storage st
    - Example: `/` → StateBackend, `/memories/` → StoreBackend
    - Longest-prefix matching for routing
    - Enables hybrid storage strategies
-   
----
-## Task Delegation (Subagents)
 
-Allows the main agent to spawn ephemeral "subagents" for isolated multi-step tasks.
+## Task delegation (subagents)
+
+The harness allows the main agent to create ephemeral "subagents" for isolated multi-step tasks.
 
 **Why it's useful:**
 - **Context isolation** - Subagent's work doesn't clutter main agent's context
@@ -88,11 +87,9 @@ Allows the main agent to spawn ephemeral "subagents" for isolated multi-step tas
 - Example: code-reviewer, web-researcher, test-runner
 - Configure via `subagents` parameter
 
----
-
-## Conversation History Summarization
+## Conversation history summarization
 
-Automatically compresses old conversation history when token usage becomes excessive.
+The harness automatically compresses old conversation history when token usage becomes excessive.
 
 **Configuration:**
 - Triggers at 170,000 tokens
@@ -104,11 +101,9 @@ Automatically compresses old conversation history when token usage becomes exces
 - Preserves recent context while compressing ancient history
 - Transparent to the agent (appears as a special system message)
 
----
-
-## Dangling Tool Call Repair
+## Dangling tool call repair
 
-Fixes message history when tool calls are interrupted or cancelled before receiving results.
+The harness fixes message history when tool calls are interrupted or cancelled before receiving results.
 
 **The problem:**
 - Agent requests tool call: "Please run X"
@@ -126,23 +121,20 @@ Fixes message history when tool calls are interrupted or cancelled before receiv
 - Gracefully handles interruptions and errors
 - Maintains conversation coherence
 
----
+## To-do list tracking
 
-## Todo List Tracking
-
-Provides a `write_todos` tool that agents can use to maintain a structured task list.
+The harness provides a `write_todos` tool that agents can use to maintain a structured task list.
 
 **Features:**
 - Track multiple tasks with statuses (pending, in_progress, completed)
 - Persisted in agent state
 - Helps agent organize complex multi-step work
 - Useful for long-running tasks and planning
 
----
 
 ## Human-in-the-Loop
 
-Pauses agent execution at specified tool calls to allow human approval/modification.
+The harness pauses agent execution at specified tool calls to allow human approval/modification.
 
 **Configuration:**
 - Map tool names to interrupt configurations
@@ -154,11 +146,10 @@ Pauses agent execution at specified tool calls to allow human approval/modificat
 - User verification before expensive API calls
 - Interactive debugging and guidance
 
----
 
-## Prompt Caching (Anthropic)
+## Prompt caching (Anthropic)
 
-Enables Anthropic's prompt caching feature to reduce redundant token processing.
+The harness enables Anthropic's prompt caching feature to reduce redundant token processing.
 
 **How it works:**
 - Caches portions of the prompt that repeat across turns