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

Annotations only declare readOnlyHint and openWorldHint; the description adds substantial behavior beyond that, including the conditional `fullContent` fetch tied to subscription settings, the explicit absence of a read-marking side effect, and the not-found failure condition for missing or invisible entries.

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?

Three sentences, each carrying distinct information: what is returned, when to use it, and the failure/side-effect profile. The payload description is front-loaded before routing and error details, with no redundant restatement of the tool name.

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 tool with no output schema, the description fully covers what matters: the shape of the returned content, the conditional `fullContent` case, the absence of mutation, and the error condition. Nothing an agent needs to call it 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% for the single `entryId` parameter, so the baseline is 3. The description goes slightly further by explaining where valid IDs originate (list_entries, save_article, upload_article) and by tying the not-found error to ID validity and visibility.

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 specific verb and resource ('Get one entry with its content') and enumerates what comes back: original HTML, cleaned HTML, and conditional `fullContent`. It is clearly distinguishable from list_entries, save_article, and upload_article, which it names explicitly.

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?

Explicitly says to use this to read an entry whose ID came from list_entries, save_article, or upload_article, giving the prerequisite for obtaining the required parameter. It also names the alternative for the adjacent action ('Doesn't mark it read (use mark_entries_read)'), so the boundary with a sibling tool is stated rather than inferred.

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