# Google's Gemini 3 Models Combine Web Search with Custom Tools

> Google's Gemini 3 models now integrate the built-in `google_search` tool with custom function tools, a functionality absent in earlier Gemini 2.x versions.

By PrimaryBrief newsroom · Published 2026-10-26T08:43:57.199437Z
Canonical: https://primarybrief.com/article/google-s-gemini-3-models-combine-web-search-with-custom-tools-9a218460

Google's Gemini 3 models now allow their `google_search` tool to be combined with custom function tools, a capability that was not available in previous Gemini 2.x models [12][13]. This integration, confirmed by Google documentation as of October 2026, means developers can blend real-time web data with tailored functionalities [13][14].

This development matters because it broadens the scope for developers to create more dynamic and factually accurate AI applications. By combining web search with custom functions, applications can access up-to-date information while performing specialized tasks, enhancing reliability and utility for users [14].

## What the records show

Previous documentation indicated that Gemini 2.x models had a limitation preventing the `google_search` tool from being combined with custom function tools in a single request [11][12]. The `adk.dev` documentation noted that the `google_search` tool could only be used by itself within an agent instance [11].

However, this changed with Gemini 3 models. `github.com` stated on August 24, 2025, that "Gemini 3 added" this capability, overcoming the prior API limitation [12]. By October 13, 2026, `google.dev` explicitly confirmed that "Gemini 3 models also support combining these built-in tools with custom tools (function calling)" [13].

## The timeline

Prior to Gemini 3, the architecture of Gemini 2.x models restricted the `google_search` tool to operate in isolation from custom functions [11][12]. The introduction of Gemini 3 models marked the point when this restriction was lifted [12][13]. As of October 13, 2026, official sources confirm that Gemini 3 models fully support the combination of built-in tools, including `google_search`, with custom tools [13].

## What changed and for whom

For developers and users of Gemini models, the ability to combine `google_search` with custom tools represents an advancement. Developers can now design applications that perform real-time web searches and execute specific custom functions simultaneously within a single request [13][14]. This removes a previous hurdle that required separate calls or complex orchestration to achieve similar results, which was a challenge for Gemini 2.x users [11][12]. The new functionality means Gemini models can provide more accurate and up-to-date answers by leveraging current web content, while also performing specialized tasks defined by custom code [14].

## What the subject has said publicly

Google's developer documentation, including `google.dev`, has affirmed that Gemini 3 models facilitate the combination of built-in tools like Google Search with custom tools [13]. This documentation, updated as recently as October 13, 2026, highlights the expanded capabilities for developers [13]. `google.com` outlined on October 14, 2026, the benefits of Grounding with Google Search, emphasizing its role in increasing factual accuracy, accessing real-time information, and providing verifiable sources [14]. Public statements from `github.com` on August 24, 2025, also acknowledged that Gemini 3 specifically addressed the limitation seen in Gemini 2.x models regarding tool combination [12].

## What we could not confirm

We could not confirm the exact date in 2025 when Gemini 3 models were first released to the public or developers with this specific tool combination capability. The evidence indicates it was introduced sometime after August 24, 2025, but does not provide a precise launch date [12].

## Evidence cited
1. Population Boom: Charting how we got to nearly 8 billion people (weforum.org) — https://vertexaisearch.cloud.google.com/grounding-api-redirect/AUZIYQEcP6KyJ1hyg_0Q2_N86bj58ZTGkTY9_E26Q81aJ7uMq5y8h-31YjAn9ozs00lSQjXYR6O_Q09Daumi1NuaGUG-Ww4Ez3KekF-cm8D-qf878TZIW5GMblUsM9YHG5QtDY0X368G5mxEiLm2SIMwux6vn6_AWm6sRO3t2gc6r3zZoWUCas_exDwl_qeENFXF1pDT
2. World Population Estimated at 8 Billion (census.gov) — https://vertexaisearch.cloud.google.com/grounding-api-redirect/AUZIYQFtwQk4yLSmlyi1HtRO7njJJ5vvgaz3_pwqYfqwtz8F_2pGe2iT-WGcdvBlkM6DzEOcHYchu15mK8jgfw6h-vkxFVetquh0vIiK4dZc-kq6-2vGIQKy33JWcApxZ8NTfDw9-x01DygPlauLdpA2dRRcZe0yyINaB6vyLp8-6JaFkO7LLFjIlBjHFKnIU0jy1_JRYE-_kEGA
3. State of World Population 2023 - 8 Billion Lives, Infinite Possibilities | United Nations Population Fund (unfpa.org) — https://vertexaisearch.cloud.google.com/grounding-api-redirect/AUZIYQGfBTXcmqp83uGZ6lUCJQphGklWUcytZ88Vmhnssw0_Wc2b7k10BLKXceB-MM5395iJcrT4b4V6eD3S_v-cGdBNWryeixADSaZrH_rLL9aOxQBxFQ335mxOfQYdv3-C9SbVN5kokCwEE1jTmuSml1IfwoqbtXDsQ3P-4BBZ9rA03SoYV9s3g9XJiP_k6IXtmwdQnsfo0M4vbsd-z2k3bX6v
4. 2024년 세계인구 80억명 초과 (youtube.com) — https://vertexaisearch.cloud.google.com/grounding-api-redirect/AUZIYQFmHx4uaDecn_dJFMSEkX9fo19shu3mpBiXznwlF95kc7yzHVlFULaS5L62-gc1WDzdUAbMPYRzvjrTUfMH10YkD8UQ7pZ3sAJyxCUJeGl9JB379OgEArdO_sLwFCxXM9jyiLeV19k=
5. World population - Wikipedia (wikipedia.org) — https://vertexaisearch.cloud.google.com/grounding-api-redirect/AUZIYQFnbad9i-3ro-O7SGuCpyH0jJeGddZierQJPcrYSGPQso9LRoiFWuwrOk-OiMs7xehzvTjS5ZqAWJ6gdP0VjqViZ6hxGV6Oj5Z5TwwDpJEnG0t2dJdy_TBspc5Dq8Mj70ejReLZusR-Rmk=
6. Population Boom: Charting how we got to nearly 8 billion people (weforum.org) — https://www.weforum.org/agenda/2021/12/world-population-8-billion-demographics-data/
7. World Population Estimated at 8 Billion (census.gov) — https://www.census.gov/newsroom/press-releases/2023/world-population-estimated-at-8-billion.html
8. State of World Population 2023 - 8 Billion Lives, Infinite Possibilities | United Nations Population Fund (unfpa.org) — https://www.unfpa.org/swp2023
9. [SBS뉴스] 2024년 세계인구 80억명 초과... (youtube.com) — https://www.youtube.com/watch?v=O130nL2F6a0
10. World population - Wikipedia (wikipedia.org) — https://en.wikipedia.org/wiki/World_population
11. adk.dev (adk.dev) — https://vertexaisearch.cloud.google.com/grounding-api-redirect/AUZIYQEZNGbsLRGs5Bv6v_28P7diNOeA8v_Yes3yYum3GbBsYhYHDbz1ch2CM6qQcjGlt6POEWk8L7dBD-SvzRKurHsQBr8SDxTWPRXilPX2yiQ_aYN7F1Qsj6SGDPEWPZb6jIJrY66J0F4=
12. github.com (github.com) — https://vertexaisearch.cloud.google.com/grounding-api-redirect/AUZIYQEnTwP34YxYZASNstY8W8rfnGVIW5Ca64IHyJeVM4UPqjoQF8wWxXCj4fcXi3K2hnBjgcuf8L1ufVKmtVycXSFakQBtSfizDxLKQkqexrSFzkEyB-sljZnkRwxkeL_TSN4eUvw=
13. google.dev (google.dev) — https://vertexaisearch.cloud.google.com/grounding-api-redirect/AUZIYQHAFoOli7O-QAcE0gGKbkCOlJGbu0aFizPDtBTbriIosnmVIjAtehdbkwlC7Q46TNSXrV-XtXEE_b6zZL4qcfP0xv1IawCn8C0av2pP60bgqQPvVUlp-jBLUOa4LEJ4oHctdK6O5kP-SZZ8qgXQNA==
14. google.com (google.com) — https://vertexaisearch.cloud.google.com/grounding-api-redirect/AUZIYQFNHtRjRooXJGnKxkeg1ZcZFGnv00waE3VKTZ9UcyX_htvIpq_dNJcyCWYJJrvWtn2n3xkhDtoO3WJiJZ0c1pVRWvhoh3D9-L3d1iFCpps_StkTGCe9nLuUnYlSTY_7Wh3iFZb9zQRSxVRi5F8Zewn7x1jQHlZYVdFru8xp