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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so safety and external reach are covered. The description adds the search-syntax flavor and the global-vs-repo scope, but says nothing about GitHub's strict search rate limits, result ordering, or pagination behavior.

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?

Two tight sentences with the scope constraint front-loaded and a concrete syntax example appended. Nothing is redundant and the reader knows what the tool does after the first clause.

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?

With four fully documented parameters, a required query, and no output schema, the definition is nearly self-sufficient. The only real gap is that result shape and rate-limit behavior are unaddressed, which a search tool against GitHub's throttled API arguably warrants.

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%, including enum values and defaults for type and limit, so the baseline is 3. The description's example query ("label:bug is:open login") reinforces the qualifier syntax already documented in the query parameter, adding illustrative value rather than new semantics.

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 ("Search") and resource ("GitHub issues, pull requests or code") plus the scope distinction of global vs. single-repo. This separates it from list-style siblings such as github_list_issues and github_list_prs, though it never names an alternative explicitly.

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?

Usage is implied by "Search GitHub for..." and the syntax example, giving the agent a clear sense of when the tool applies. However, there is no explicit when-not guidance and no named alternative (e.g., github_list_issues for unqueried listing), so routing must be inferred.

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