GitHub MCP Server

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

No annotations are provided, so the description carries full burden. It states a mutation action ('mark... as read') but doesn't disclose behavioral traits like whether this requires specific permissions, if it's idempotent, what happens to future notifications, or any rate limits. The description is minimal and lacks crucial context for a mutation tool.

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 a single, efficient sentence with zero wasted words. It's front-loaded with the core action and resource. Every word earns its place, making it maximally concise while still conveying the basic purpose.

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?

Given the tool has an output schema (which handles return values) and 100% schema coverage for its single parameter, the description's minimalism is partially acceptable. However, as a mutation tool with no annotations, it should provide more behavioral context about side effects, permissions, or idempotency. The description is adequate but leaves clear gaps.

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%, with the single parameter 'last_read_at' well-documented in the schema as an ISO 8601 timestamp. The description adds no parameter information beyond what the schema provides. With high schema coverage, the baseline score of 3 is appropriate as the 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 verb ('mark') and resource ('all notifications') with the specific action 'as read'. It distinguishes from the sibling 'mark_thread_read' by specifying 'notifications' rather than 'thread', but doesn't explicitly contrast them. The purpose is unambiguous but lacks explicit sibling differentiation.

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 provides no guidance on when to use this tool versus alternatives like 'mark_thread_read' or 'list_notifications'. There are no prerequisites, exclusions, or context about when this operation is appropriate. The agent must infer usage from the name alone.

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