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

readOnlyHint=true already establishes this as a safe read, so the bar is lower, and the description still adds real disclosure: money fields require the task:costs permission and are otherwise null, null salary/bonus values are hidden from the payload, and rates/amounts are assessment-scoped rather than comment-scoped. These are permission and null-handling traits an agent could not derive from the annotations or schema. It stops short of describing payload shape or size limits, so it isn't 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?

It is a single dense run-on with an embedded list, but the purpose is front-loaded in the first clause and every subsequent clause carries distinct information (payload contents, permission caveat, null handling, scope caveat). No sentence is filler, though the list-heavy packing makes it slightly harder to scan than an ideally structured definition.

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 burden of describing return contents and does so at field-group granularity, plus the permission precondition and null semantics. For a zero-required-parameter read tool this is close to sufficient; the remaining gaps (payload size, whether cost fields appear when permission is absent, meaning of "returns") are minor.

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 ID/key/stage parameters and the work-default are already fully documented in the schema, establishing a baseline of 3. The description confirms the work-stage default and ties cost fields indirectly to caller permissions, which is useful but does not add syntax or selection meaning beyond the schema's own enum and default notes.

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 ("Returns the data for evaluating a task stage") and enumerates the payload precisely: spec and result, assignee with level, rates, time/cost, plan by status, returns, bugs and regressions with fix cost, commits, previous evaluation. That is far more informative than a tautology like "task_evaluate data". It does not, however, name or contrast against overlapping siblings such as task_context, task_commits, or task_evaluate, so an agent cannot fully discriminate without opening schemas.

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?

"when the user asks for a work evaluation" gives a usable trigger condition, which is more than implied usage, but it does not exclude or route against clearly adjacent siblings (task_evaluate for actually filing an evaluation, task_context, task_commits, evaluation_rules). The closing note "for the assessment, not for the evaluation comment" hints at a distinction but never names the alternative tool, leaving the boundary to inference.

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