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

With no annotations provided, the description carries the burden of behavioral disclosure. It does disclose that results are compact and include title, source, and message count, which is useful. However, it does not mention ordering, pagination, potential absence of session IDs, or whether the operation has any side effects.

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 a single front-loaded sentence with no wasted words. It states the operation, scope, and output shape efficiently in one line.

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?

The tool is simple, but there is no output schema, so the description must clarify what is returned; it does mention the compact fields. Still, it leaves gaps such as whether sessions are sorted, whether the list is paginated, whether IDs are included, and what happens when there are no sessions. These are not addressed.

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% for the single projectId parameter, though the schema only says 'Project ID'. The description adds the context that the parameter selects the owning project for the session list, but it does not provide meaningful additional semantic detail beyond that. Baseline 3 is appropriate given full schema coverage.

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 uses a specific verb and resource: 'List chat sessions of a project'. It also clarifies the return is a compact summary with 'title, source, message count', which distinguishes it from more detailed session tools like get_chat_session. However, it does not explicitly name any sibling tool for contrast.

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 makes the basic use case clear: call this when you need chat sessions for a project. It does not state when not to use it or mention alternatives such as get_chat_session for a single session's full detail. Usage is implied rather than explicitly contrasted.

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