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

The readOnlyHint annotation already signals a safe read operation; the description adds valuable context beyond that by listing the detailed return contents (children, acceptance criteria with evidence coverage, history log, etc.) and a caution to not browse the UI for URL extraction. No contradiction with annotations.

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 with zero waste: the first states the function and output, the second gives usage guidance. The key purpose is front-loaded, and every clause earns its place.

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?

For a single-parameter read-only tool with no output schema, the description compensates by listing the response fields and giving precise parameter derivation. It doesn't mention error handling or not-found behavior, which is minor but not a blocker for correct invocation.

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?

The schema already describes goalId as 'UUID цели' (goal UUID) with 100% coverage, so the baseline is 3. The description elevates this by giving a practical way to obtain the UUID (extract after /goal/), adding meaning beyond the schema's generic label.

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 full details of a single goal') and enumerates the exact fields returned, making its function unmistakable. It also positions itself relative to siblings ('primary drill-down tool after goal-list or goal-tree'), clearly distinguishing it from list/tree tools.

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 explicit context for when to use it (after goal-list or goal-tree) and provides a concrete scenario (Planner goal URL) with step-by-step guidance (extract UUID after /goal/). It does not name alternatives like goal-summary, but the primary use case is well-defined.

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