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

Annotations already mark the tool read-only, and the description matches that. It adds useful behavioral detail beyond the schema: the tool exposes site owner intent, data-retention settings, and well-known keys with semantic meanings, including the 'notes' convention. 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?

The description is compact and front-loads the core purpose before enumerating well-known keys. Each sentence contributes value, including the usage directive. The parenthetical about notes is slightly dense but still efficient.

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 read-only tool with an output schema and a single optional parameter, the description is largely sufficient. It tells the agent what the tool returns, what the keys mean, and when to call it. The main gap is that data-retention settings are mentioned but not elaborated, though the output schema likely covers that.

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 single parameter `site` is fully documented in the schema, including when to omit it and how to derive its value from the script tag or list_sites. The description adds no parameter-level meaning, but the schema coverage is 100%, so the baseline of 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?

The description identifies the resource ('what a site is and what the owner wants from it') and the operation (retrieve context, including data-retention settings). It also lists well-known keys, making the tool's output concrete. It is clear, though it does not explicitly contrast itself with siblings such as update_site_context or list_sites.

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 description gives explicit timing guidance: 'Read this before making recommendations.' It also explains that the notes key holds open agenda items to check at session start. It does not name alternatives or when not to use this tool, but the context is discernible.

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