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

Annotations already cover the safety profile (readOnlyHint=true, openWorldHint=false), so the bar is lower, and the description still adds real context: results come from the vendor's own page and each entry carries an end date and source, which speaks to provenance and staleness. It omits result count, pagination, and refresh cadence, which keeps it from 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 tight sentences with zero filler, and the core purpose (active offers, and from whom) is front-loaded before the provenance detail. Nothing needs to be cut.

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 zero-required-parameter, read-only listing tool with no output schema, the description tells the agent what to expect in each result (end date, source) and what the catalog covers. Only minor gaps remain: no pagination or result-volume expectations, and no mention of filtering by vendor.

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% and both parameters are optional and self-documented, so the baseline is 3. The description echoes the `kind`-style categories (discounts, free access, extra usage, credits, student, startup, open-source) but says nothing about the `agent` filter or how the two combine.

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 (active official deals/offers from AI agent and tool vendors) and enumerates the categories returned, so an agent knows exactly what this returns. It is distinguishable from data-oriented siblings like model_prices or find_tools, though it never states its verb (list/retrieve) or explicitly contrasts itself with those siblings.

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?

There is no when-to-use statement, no exclusions, and no named alternative. The closest thing to guidance is the enumeration of offer categories, which an agent can loosely infer maps to the `kind` filter, but nothing tells it when to pick current_deals over model_prices, price_history, or limit_resets.

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