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

With no annotations, the description must carry the full behavioral burden. It discloses one real trait — results are ordered most-starred first — but nothing about where results come from (presumably GitHub repos), whether output is a list of repos with names/URLs/stars, or any auth/rate-limit constraints. For a search tool with no output schema, this leaves the agent guessing at the return shape.

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 ~20-word sentence with no filler; the input examples and the sort order are both front-loaded. It reads as an efficient fragment rather than a complete spec, which is a gap but not verbosity.

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?

The tool is simple (3 params, no nesting, no output schema), and parameters are fully documented in the schema. The remaining meaningful gap is the result shape: an agent cannot tell from the description what fields come back, which matters more because there is no output schema to fall back on.

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 limit, locale and product are all documented in the schema; the baseline is 3. The description adds only an example product value, which slightly reinforces the 'product' parameter but adds nothing about limit or locale 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 names a specific resource (open-source alternatives to a named commercial product) and gives three concrete examples, which clearly distinguishes it from sibling repo/collection search tools. It is a noun phrase rather than a verb-led sentence, so the action ('find') is only implied by the tool name, not stated in the description.

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 the examples ('Notion', 'Google Analytics', 'Zapier'), which show the expected input domain, and the sibling set (search_repos, trending, get_repo) is clearly a different kind of lookup. However, there is no explicit statement of when to prefer this tool, nor any exclusion or prerequisite (e.g. whether the product must be commercial, whether a GitHub account is needed).

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