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

Annotations already declare readOnlyHint=true, covering the safety profile. The description adds valuable behavioral context by disclosing the response shape — each node includes id, title, status, priority, type, progress, and nested children — and by explaining how projectId and rootId alter the scope of the tree. It stops short of details like ordering or progress format, but the added value is solid.

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, each earning its place: the core action, the optional filters, and the node shape. The primary purpose is front-loaded and there is zero filler.

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 compensates by specifying the exact node fields and nested structure. Both parameters are explained, defaults are implied, and the readOnlyHint annotation covers the safety profile. Only minor edge cases — such as behavior when both filters are supplied or the progress value format — remain unaddressed.

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 still adds meaning by assigning each parameter a behavioral role: projectId 'scopes to one project' and rootId 'gets a subtree', which also implies the defaults (all projects, full hierarchy). This is richer than the terse schema descriptions.

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: 'Fetch the full goal hierarchy as a nested tree.' The emphasis on 'full' and 'nested tree' with a 'nested children array' clearly distinguishes it from flat-list siblings like goal-list and single-object siblings like goal-get.

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?

The filtering semantics ('scope to one project' vs 'get a subtree') provide clear context for when to narrow the call, and the first sentence states the primary use case. However, it never names alternatives such as goal-get or goal-list, nor states when not to use this tool, so the agent must infer selection from the tree-shaped requirement.

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