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

Annotations already declare readOnlyHint=true and openWorldHint=false, yet the description still adds real behavior: the matching mechanism (keyword match over summaries and tags), the result cap (up to 3), the ordering rule (free packs first), and the per-result rationale. It omits empty-result handling and how strict the keyword match is, keeping it below a 5.

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 sentences, no filler, and the most important information (what comes back and how it is ranked) is front-loaded. Every clause contributes either scope, count, mechanism, or ordering.

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 no output schema, the description must carry return-value information, and it does: count cap, inclusion of why-they-match, and free-first ordering. It stops short of describing the fields of each returned pack or what a zero-match response looks like.

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 coverage is 100% and the single parameter already says 'one or two sentences'. The description only slightly enriches this by revealing that matching is keyword-based, which hints that concrete task terms beat vague prose. Baseline 3 applies since 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?

States a specific verb+resource (recommend matching packs) plus the input basis (a short task description) and output shape (up to 3 matches with reasons). It is clearly distinguishable from list_packs/get_free_pack by its ranking behavior, though it never names a sibling to sharpen the contrast.

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 opening clause gives a concrete trigger condition: the user describes what they are trying to do and wants suggestions. It does not state exclusions (e.g., when the pack name is already known, call get_free_pack directly), so an agent must infer the boundary against siblings.

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