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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower. The description adds real behavioral context beyond them: expected response size (~6–10k characters), what compact returns versus full, and the composition rule for 'core'. It omits any mention of cost, latency, or failure modes, so not 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?

Purpose is front-loaded and only three sentences, but the final sentence is a dense run-on packed with nested parentheticals and internal shorthand ('core' = ...), which is hard to parse on first read. It is information-dense rather than wasteful, but structure suffers.

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 and a large nested context object, the description usefully compensates by describing the default response shape and size, and the schema itself documents all context keys at 100% coverage. It stops short of describing the conceptual shape of the returned route (stages/gates/work items) or validation failure behavior, which the schema only partially implies.

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, but the description genuinely extends it by explaining the 'core' strength tier (context rules, flags, gate-critical artifacts; max 8 items per stage; producer-first ordering) and the stage+format interaction — semantics not present in 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 opening sentence establishes scope ('route from presale to closure for a project context') and the rest details what the route contains (ids by strength, names dictionary, core items, gate evidence per stage), so an agent can tell it produces a routed project plan. It never differentiates itself from siblings like validate_plan or when_to_use, and 'route' as a verb is jargon-heavy, keeping it below 5.

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?

It gives invocation guidance for modes (default compact vs format:'full' with a single stage for reasons/avoid texts, and what 'core' means), which implies how to call it. However there is no when-to-use vs alternatives guidance — nothing tells the agent why to call plan_project rather than validate_plan, check_gate or when_to_use.

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