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

Annotations already declare readOnlyHint=true, so the description need not restate safety; it does add real value by disclosing that recommendations are 'rules-based' and include 'live store links and prices', which tells the agent the output is advisory and commercially current. However, 'live' prices sit in mild tension with openWorldHint=false, and the description says nothing about determinism, latency, or what the recommendation payload actually contains.

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, front-loaded with the purpose and followed by the differentiating detail about rules and live pricing. The trailing fragment 'Rules-based, with live store links and prices' is slightly clipped but still earns its place as behavioral signal.

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 five optional parameters and no output schema, the description must carry more of the burden of explaining what comes back. It does state that a recommended path plus store links and prices are returned, but it does not describe the shape of the recommendation or what happens when inputs are omitted (all parameters are optional).

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 mid-range (roughly 60%: wants, watch_on and already_use are documented, household_size and budget_monthly_usd are not), so the schema carries most of the load. The description loosely maps to inputs via 'how someone watches' (watch_on) and 'what they want' (wants) but adds no format, unit, or interaction detail 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?

The description opens with a specific verb and resource: 'Suggests which ElfHosted path fits...', and enumerates the candidate outcomes (Stremio + private AIOStreams, Plex/Emby/Jellyfin library, Flex for apps). That is enough for an agent to distinguish it from siblings like browse_apps or compare_apps, though it never names those siblings explicitly.

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 rather than stated: an agent can infer this is the entry point for 'which plan/path should I pick', keyed off watching habits and wants. There is no explicit when-to-use vs when-not guidance and no pointer to alternatives such as compare_apps or browse_apps for agents who already know what they want.

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