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

Annotations already declare readOnlyHint=true, and the description reinforces it with 'writes nothing' while enumerating exactly what is returned (specs, task results, workspace guidelines). It adds useful return-shape context beyond the safety hint, though it doesn't discuss pagination or limits on the batch size.

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?

Front-loaded with the primary purpose, then details of return content and mode behavior in a compact block. Slightly dense and partially redundant with the mode enum in the schema, but every sentence carries information.

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 usefully spells out the returned payload (feature.spec, tasks[].spec, tasks[].result, instructions) and the analyze/apply distinction, which is essential for a 7-parameter tool. Minor gaps remain around defaults for basis and chatLimit that live only in the schema.

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 every parameter is already documented in the schema. The description largely restates mode semantics and the includeTaskIDs behavior ('full contexts with chats of tasks with discrepancies') with little added meaning beyond the schema text, so the baseline 3 applies.

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?

States a concrete verb and resource: returns the context (feature.spec, tasks[].spec, tasks[].result, guidelines) needed to update a feature's spec. The feature-level scope clearly separates it from the sibling task_spec_sync, so an agent can pick between them without opening either schema.

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?

Gives explicit mode-based usage: 'mode=analyze - differences and a full new version without saving' versus 'mode=apply - when the user asks to apply the update.' That is a clear when-to-use rule, though it does not name an alternative tool or state exclusions.

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