Gemini MCP Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries full burden for behavioral disclosure. While it mentions the tool 'Run[s] a Gemini session' and lists configuration parameters, it doesn't describe what the session entails, whether it's interactive or single-turn, what happens to the conversation state, authentication requirements, rate limits, or error behavior. The description provides basic functional information but lacks important behavioral context for a tool with 7 parameters.

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?

The description is appropriately sized and front-loaded with the core purpose. The first sentence establishes what the tool does, followed by relevant configuration details. There's minimal wasted text, though the parameter listing could be more concise given the schema already documents them thoroughly. Overall structure is logical and efficient.

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?

For a tool with 7 parameters, no annotations, no output schema, and siblings with similar names, the description is incomplete. It doesn't explain what a 'Gemini session' entails, how it differs from sibling tools, what the expected behavior/output is, or important operational constraints. The comparison to Codex helps but doesn't compensate for the significant gaps in behavioral and contextual information.

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%, so the schema already documents all 7 parameters thoroughly. The description lists the parameters and mentions they 'match the Codex Config struct', which adds some conceptual context. However, it doesn't provide significant additional semantic meaning beyond what's already in the schema descriptions. The baseline of 3 is appropriate when schema does the heavy lifting.

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 clearly states the tool 'Run[s] a Gemini session' and specifies it uses 'Google Gemini 3 Pro Preview', which is a specific verb+resource combination. However, it doesn't explicitly distinguish this tool from its siblings (gemini-image, gemini-reply, gemini-video-check, gemini-video-generate), which appear to be specialized variants. The comparison to 'Codex' provides helpful context but doesn't fully differentiate from sibling tools.

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?

The description implies usage context through the comparison to 'Codex' and mentions configuration parameters, but provides no explicit guidance on when to use this tool versus its siblings or alternatives. There's no mention of prerequisites, typical use cases, or when-not-to-use scenarios. The implied context is helpful but incomplete.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.