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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered elsewhere. The description adds one genuinely useful behavioral fact — the whole list comes back with no pagination — plus the returned fields, but says nothing about ordering, size limits, or what happens with zero follows.

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, front-loaded with the action and payload, then the no-pagination caveat, then the routing hint. Nothing is repeated from annotations and no sentence is filler.

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?

Output schema covers the return shape and annotations cover the safety profile, so the description only needed to add scope and routing — which it does. It stops short of clarifying ordering or how 'state' and 'filters' should be interpreted, a minor gap for a zero-parameter listing tool.

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 tool takes no parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The schema imposes no filtering or pagination options, which is consistent with the stated full-list behavior.

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 ('List all followed companies') and enumerates what each entry contains: filters, state, unread counts. It also draws the boundary against job search, so an agent can tell which concept it is retrieving without inspecting 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?

The closing sentence routes the agent correctly: following is for future matching openings, Search is for jobs already indexed. That is real when-to-use-this-vs-alternative guidance, though it doesn't address the nearest sibling, following.openings.list, which operates on the same followed companies.

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