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

With no annotations, the description carries the full burden and does disclose the return shape plus a genuine behavioral constraint: entry ids are unique within a timeline, not across the site. It does not cover auth needs or rate limits, but for a read-only detail fetch the critical scoping behavior is disclosed.

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?

Two sentences, front-loaded with the payload description and closed with the usage trigger and scoping caveat. The first sentence is long due to the field enumeration, but every element listed is meaningful and no sentence is wasted.

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?

There is no output schema, so the description must describe the return value — and it does so thoroughly, including source quotes and links. Combined with the id-uniqueness caveat, an agent has everything needed to call this correctly.

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%, so baseline is 3, but the description adds meaning beyond the schema: it explains why slug is required alongside id (id uniqueness is per-timeline, not global). That is real semantic value the schema's own 'The timeline the entry sits on' does not fully convey.

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 names a specific verb and resource and then enumerates exactly what 'in full' means: summary, type, parties, sources with outlet, publication date, verbatim quote, relations, and cross-timeline links. That enumeration distinguishes it clearly from search_entries (list-level) and get_timeline (structure-level) siblings.

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 states the trigger: use after search_entries or get_timeline has found an entry and you need exact wording and a source URL to cite. It also names the prerequisite for correct invocation (pass the slug the entry came from), leaving nothing to inference.

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