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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive, so safety needs no restating; the description instead adds substantive behavioral context about what it surfaces, which matters because there is no output schema. It does not say what happens when neither projectId nor workspaceId is supplied, leaving the resolution default implicit.

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 sentences, no filler: the payload is described first, then the call conditions, which is the right front-loading. The first sentence is a long enumeration, but every listed item is meaningful for an agent deciding whether the call answers the user's question.

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 carries the return-value burden by enumerating the fields. The remaining gap is the zero-required-parameter design: both identifiers are optional, yet the description never states what plan applies when they are omitted, which an agent needs before calling bare.

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%, with both parameters fully documented including provenance (from list_projects / list_workspaces) and the multi-workspace requirement, so the baseline of 3 applies. The description adds no parameter-level 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 names the resource and enumerates the exact contents returned (plan name, row caps, estimate inclusion, history/trend windows, research quota used/left), so an agent knows precisely what 'access' means here rather than guessing from the vague tool name. It doesn't distinguish itself from nearby siblings like get_plan_options or start_plan_upgrade, which is the only thing keeping it off a 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?

Explicit triggers are given: call it when a result returns locked fields and the user asks why, or before sightglass_research_company. That is concrete context plus a named downstream tool. There is no when-not guidance or mention of the plan-related siblings, so it falls short of full alternative routing.

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