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

Beyond the readOnlyHint/openWorldHint annotations, it discloses result quantity (max 3), ranking policy (free packs preferred), and the shape of returned data (why-they-match plus paid_upgrade for free hits). That is genuinely useful behavioral context an agent cannot get from the annotations.

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 dense sentences, front-loaded with the core action and result cap, then the ranking and return-field nuance. No filler or repetition.

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 does the work of explaining the return payload (matching packs, why-they-match, paid_upgrade), which is the key gap it needed to fill. It is only slightly incomplete on edge cases such as zero matches or how ranking ties break.

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?

Only one parameter and schema description coverage is 100%, so the schema already carries the meaning of `task`. The description re-states the same idea ("short description of what the user is trying to do") without adding format or granularity guidance beyond the schema.

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 and resource (return up to 3 matching packs) and discloses the matching mechanism (keyword match over summaries and tags), so it is clearly not a plain listing tool like list_packs. It never names a sibling, so distinction is inferable rather than explicit.

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?

Implies the usage context ("Given a short description of what the user is trying to do") and hints at a follow-on flow with paid_upgrade "for when the user wants more", but never states when to prefer this over list_packs or get_free_pack, nor any exclusions such as what happens on no match.

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