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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful context beyond that: the retrieval mechanism ('hybrid semantic + keyword retrieval with operation-aware reranking') and a privacy guarantee ('Nothing you send is stored'). Those are behaviors an agent could not infer from annotations or schema.

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?

Three sentences, no filler, and the core purpose is front-loaded before mechanism and privacy details. Every sentence adds distinct information (what it does, how to call it, how it works, data handling).

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 correctly explains what comes back (a ranked minimal set plus token savings). Input source, retrieval method, and privacy posture are all covered. Minor gaps remain around ranking/tie behavior and error cases, but nothing essential to a correct invocation is missing.

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%, so the baseline is 3. The description earns above baseline by clarifying the provenance of the otherwise opaque 'tools' array ('from tools/list across your servers') and by describing the return shape ('minimal set ranked by fit, with the tokens saved'), which the schema does not convey.

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 ('Pick which of YOUR connected tools a task needs') plus the outcome ('load a handful of definitions instead of all of them'). An agent immediately understands the job. It does not, however, differentiate itself from near-siblings like discover_tools, route_task, or route_tasks, which appear to overlap in scope.

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?

Gives a clear trigger condition (loading a subset of definitions rather than all) and explains the input flow ('pass the task and the tool definitions you have from tools/list'). But with route_task, route_tasks, discover_tools and preflight_tools in the sibling set, the absence of any explicit when-to-use-this-vs-that guidance leaves the agent guessing.

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