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

Annotations already declare the safety profile (readOnly, idempotent, non-destructive, openWorld), so the bar is lower, and the description adds that the response includes liveness status — useful return-behavior context given no output schema exists. It stops short of describing behavior for an unknown/expired slug.

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 front-loaded sentence with the core action first and the clarifying parenthetical after; no filler and nothing repeated from the schema.

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 one-parameter read tool with full schema coverage and no output schema, the description is nearly sufficient: it names the key, the input shape, and one salient returned attribute. Only failure behavior (nonexistent or dead-slug errors) is left unstated, a minor gap.

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%, so baseline is 3, but the description adds meaning beyond the schema by defining slug concretely as the last segment of a stackthedeal.com/deals/<slug>/ URL. That extra identification help is genuinely additive for recognizing a valid slug.

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?

Specific verb+resource (get one deal) scoped to a single entity, which cleanly separates it from the sibling list_deals and search_deals that operate on collections. The parenthetical explaining the slug's URL origin further pins down what a 'deal' is in this domain.

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 only implied: it fetches a single deal by slug, and the schema hints the slug comes from list_deals or search_deals. There is no explicit statement of when to prefer this over search_deals or what to do if only a name is known, and no when-not-to-use guidance.

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