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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint as safe. The description adds genuinely useful behavioral insight beyond those annotations: the data is dynamic and should not be cached, implying that repeated calls may return different results. This helps the agent make a freshness decision that annotations alone would not convey.

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 two short sentences with no filler. The first sentence front-loads the core purpose, and the second provides actionable freshness guidance. Every word earns its place.

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 no-parameter, read-only tool without an output schema, the description conveys the key data types (GitHub contributions and LeetCode stats) and the time-sensitive behavior. It could slightly expand on the exact response shape, but that is unnecessary for correct invocation and selection.

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?

The tool has zero parameters and schema coverage is 100% by default. The description adds no parameter-level detail, but none is needed. The baseline of 4 for a no-parameter tool is appropriate because there is no semantic gap to fill.

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 identifies the exact resource: 'Current GitHub contributions + LeetCode stats.' Although there is no explicit verb, the tool name and title ('get_activity', 'Get live activity') make the retrieval action unambiguous. It is clearly distinct from sibling tools like get_experience, get_profile, and list_posts.

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 gives clear usage context: data changes throughout the day, so the agent should call fresh each time rather than caching. It does not mention alternatives or exclusions, but this is a unique read tool with no direct sibling overlap, so absence of explicit comparison is acceptable.

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