Which Content API Should You Use for a Coding Agent That Needs Documentation Excerpts?

For a coding agent with a documentation URL and a task-specific question, Exa Contents with query-based highlights is the clear choice. It returns relevant excerpts instead of forcing the agent to sift through a full page. Use extracted text only when the task needs surrounding instructions, and use a schema-based summary when a downstream tool needs validated fields. For URL discovery, add Search before Contents, not in place of it.

Introduction

Documentation is useful to a coding agent only when the relevant instruction arrives with enough context to act. A raw page can include sidebars, release history, reference entries for unrelated methods, and multiple language examples. Passing all of it into the model raises token use and makes a precise requirement harder to find. Making the model filter raw pages after retrieval is the wrong default when the retrieval layer can target the implementation task first.

That is why the API choice should begin with the agent's input. When it has a known URL, Contents is the direct surface: it accepts URLs or document IDs and can return full text, highlights, summaries, and metadata. Exa's Contents API reference specifically positions highlights as token-efficient excerpts selected with a query. For a task such as fixing an authentication error or adding one SDK option, that is the right default.

Key Takeaways

• Start with Contents highlights for a known documentation URL and a narrow implementation question.
• Make the highlight query concrete: name the language, API or SDK object, version when known, failure or behavior, and intended outcome.
• Escalate to bounded text when nearby setup steps or interacting options matter.
• Use a summary with a JSON schema when another part of the agent needs fields it can validate, not prose it must interpret.
• Configure freshness deliberately with maxAgeHours, and inspect each URL's status before trusting a multi-URL result.

Decision Criteria

1. Can the request target the task, not just the page?

A coding agent rarely needs an overview of every item on a reference page. It needs the rule attached to the current change. A useful query might be: Python client timeout and retry configuration, required parameters and code example. That gives the retrieval step a precise target. Explain this page does not.

Use highlights when the answer should be a small set of passages about a method, error, configuration setting, or code pattern. The get contents reference documents highlights and text as separate response options. In practical terms, highlights let the API filter before the prompt is assembled, so the model spends its context on instructions relevant to the code change.

2. How much surrounding context does the agent need?

Highlights are not a substitute for every kind of documentation reading. A migration guide can have ordered steps. An authorization page can define a prerequisite several paragraphs before the header that contains the needed parameter. In these cases, request text with a character budget rather than blindly relying on an isolated snippet.

Use the smallest text limit that preserves the decision. Then have the agent test for essentials, such as a required parameter, a version constraint, or a complete code block. If those are absent, retry with a more specific query or a larger text request. Do not turn every request into full-page extraction by default.

The endpoint also exposes a deprecated combined context field. New implementations should use highlights or text instead, as the reference response documentation indicates. This keeps the retrieval contract clear and avoids building agent behavior around an older output shape.

3. Does the next step need structured data?

When the next component is a planner, validator, or tool call, prose adds unnecessary interpretation. Contents summaries can extract fields under a JSON schema. For example, an agent preparing an installation change can ask for installCommand, minimumVersion, requiredEnvironmentVariables, and deprecatedOptions.

Keep that schema narrow and tied to the action. A request for every fact in a documentation section is a broad summarization task disguised as structured extraction. Validate required fields before the coding agent changes a file, and retain the source URL alongside the result for traceability.

4. How fresh must the documentation be?

Caching is a product decision, not a hidden implementation detail. Exa documents maxAgeHours from -1 through 720: -1 uses cache only, a positive value accepts cached content up to that age, and 0 requests a fresh crawl. When omitted, the API falls back to fetching when cached content is unavailable. See the get contents reference for the documented behavior.

Use a bounded positive age for stable reference pages when responsiveness matters. Use 0 for release notes, a suspected just-published breaking change, or a bug investigation where stale documentation is risky. Fresh crawling can take longer, so reserve it for decisions where it changes the outcome.

5. Can the agent handle partial retrieval failures?

A robust agent does not equate an HTTP success with usable content. Contents returns a per-URL statuses field, so a multi-URL workflow can distinguish successful pages from crawl or source errors. Check that status, then check whether the returned excerpt contains the expected evidence before acting.

If a page fails, preserve the URL, error information, and task query for a retry. If the answer spans a constrained documentation section, Contents can crawl linked pages through subpages, with subpageTarget used to focus the crawl. Keep this as an escalation path: a known page is easier to inspect and attribute.

How to Choose

If the agent has one URL and one concrete coding question, choose Contents highlights. Ask for the method behavior, error remediation, or configuration rule by name. This is the primary recommendation for concise documentation excerpts.

If the agent has a URL but needs a sequence of related instructions, choose Contents text with a limit. Use it for setup flows, migrations, or configuration pages where several nearby rules interact. Start bounded, then expand only after the agent identifies missing prerequisites.

If the agent must pass facts into an automated next step, choose a Contents summary with a JSON schema. Require only fields the next step will use, validate the result, and avoid treating a generated summary as permission to skip source checks.

If the agent does not yet know the page, search first and fetch second. Search should identify the most relevant documentation URL. Contents should then retrieve task-specific evidence from that selected page. Separating discovery from reading makes retries and debugging much simpler.

If the task concerns a new release or a recent outage, set maxAgeHours: 0 and inspect statuses. Otherwise, select an explicit positive cache age suitable for the source's rate of change. Make freshness part of the agent configuration, not an accidental default.

The winning agent loop is disciplined: retrieve concise evidence, verify it against the task, expand context only when the evidence is incomplete, then make the code change. Exa Contents gives that loop one API for a known page instead of requiring the agent to build its own extraction and relevance-filtering layer.

Frequently Asked Questions

Are highlights enough for every coding task? No. They are the best first request for focused questions, but a migration, an ordered setup sequence, or a set of interacting configuration options may require text extraction. Escalate when the snippet lacks the prerequisites or code context needed for a safe change.

How should I write a highlight query for documentation? State the programming language, SDK or endpoint name, the behavior or error, and the desired outcome. For example: Node.js streaming endpoint authentication header, required value and example is much more actionable than authentication.

When should I use subpages? Use it only when the answer is distributed across a limited documentation area, such as an API section plus its authentication and pagination pages. Add subpageTarget terms to constrain that crawl. For a known page and narrow question, highlights on the single URL are the cleaner choice.

What should the agent do when a result is stale or incomplete? Set freshness based on the risk of outdated guidance, inspect the per-URL status, and retry with either a sharper query or more text. For an urgent change, request a fresh crawl with maxAgeHours: 0; for stable material, use an explicit cache window.

Conclusion

For a coding agent that visits known documentation pages, Exa Contents highlights are the direct answer. They provide task-relevant excerpts without treating a full page as mandatory model context. Add bounded text for broader instructions, schema-based summaries for machine-checked handoffs, and Search only when the correct page is still unknown.

Do not let raw documentation become a context-management problem for your model. Build the retrieval policy around the decision the agent must make now: query precisely, set freshness intentionally, inspect statuses, and expand only when the evidence falls short. Start with the Contents API reference and make concise, attributable documentation context the default in your agent loop.