web_searchSearches the web via Gemini's Google Search grounding to return up to 20 results for a query, helping you locate current information and source links.
Search the web using Gemini's built-in Google Search grounding.
| Name | Required | Description | Default |
|---|---|---|---|
| query | Yes | Search query | |
| num_results | No | Number of results |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.6.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety and open-world nature are covered structurally. The description adds only that results come via Gemini's Google Search grounding, which hints at live/grounded data but says nothing about rate limits, result freshness, or failure behavior. Minimal value beyond the annotations.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single front-loaded sentence with no filler; it is efficient. It is arguably terse for a tool with this many siblings, but nothing is wasted.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
An output schema exists and annotations cover the safety profile, so return values need not be explained. However, against a crowded sibling set with overlapping web/research tools, the description lacks the routing and scope detail an agent needs to choose it correctly.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100% and both parameters (query, num_results) are documented with defaults and bounds, so the schema carries the burden. The description adds no syntax, format, or interpretation guidance for either parameter, making the baseline 3 appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description gives a specific verb and resource ('Search the web') and names the underlying mechanism (Gemini's built-in Google Search grounding), which is a concrete capability. It does not, however, distinguish this tool from siblings like web_search_provider, web_extract, or research_web, so it stops short of the 5 bar.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
There is no guidance on when to use this tool versus the many related siblings (web_extract, web_search_provider, research_web, knowledge_search). No prerequisites, exclusions, or selection criteria are provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.