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

Adds substantial context beyond annotations: entries persist through regeneration, avoidThemes acts as a HARD filter on research/planning/autopilot-refill but never filters the customer's own keywords, and edits do not affect already-scheduled articles. It also states cost ('Free') and the return ('Returns the updated brief'), none of which the annotations convey.

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?

The core add/remove vs set pattern is front-loaded in the first sentence and the rest is information-dense rather than padding. It does re-list the entire field enum already present in the schema, which is mild redundancy in an otherwise tight block.

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?

All four required parameters are explained, mutation side-effects and non-effects are covered, the target site is constrained by the schema, and the return value is stated despite there being no output schema. Nothing an agent needs to invoke this correctly is missing.

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 coverage is 100%, but the description adds meaning the schema cannot: it partitions the field enum into list fields (paired with add/remove) versus scalar fields (paired with set), and prescribes entry style ('a plain subject, not a single keyword'). That is genuine semantic value beyond the enum listings.

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?

Opens with a specific verb+resource ('One edit to the research brief') and immediately enumerates the exact action/field combinations, distinguishing it from the read-side siblings get_research_brief and regenerate_research_brief. An agent knows precisely what this mutates without opening the 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 downstream effects ('changes steer the next research run and plan refill; they do not touch scheduled articles') and routes the agent to two named alternatives with conditions (preview_avoid_matches, remove_plan_entry). It lacks any guidance on when to read the brief first (get_research_brief) or when to prefer regenerate_research_brief, so not a full 5.

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