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

Annotations already declare idempotentHint=true, readOnlyHint=false, and destructiveHint=false. The description adds value beyond those by stating the linked-account requirement, plan limit, and that alerts are factual filings only—no recommendations, targets, or grey-market premium. It does not describe duplicate-company behavior, but idempotency is already annotated.

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 first sentence front-loads the action and outcome, and the following sentences compactly cover account requirement, plan limit, and content type. The factual-data disclaimer is slightly broader than the tool itself but clarifies what alert content will contain, so it 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, idempotent, non-destructive mutation tool, the description covers the action, effect, prerequisites, and constraints. It does not explain the response format, but with no output schema and low complexity, this is not a critical omission.

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%, and the schema already defines the single parameter as 'Company slug, NSE symbol, or UUID.' The description does not add parameter-specific meaning beyond naming the resource, so the baseline 3 is appropriate.

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 and resource ('Add a company to this MarketPing account's watchlist') and states the resulting effect (filings start arriving as alerts). This clearly differentiates it from sibling tools like watchlist_list, which lists the watchlist, even without naming them.

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?

Supplies useful prerequisites and constraints: 'Needs a linked MarketPing account' and 'Subject to the plan's company limit.' However, it does not explicitly say when to use this tool versus alternatives like watchlist_list or resolve_company, nor does it provide any 'when not to use' guidance.

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