list_sessions_tool

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

With no annotations, the description carries the full behavioral burden. It usefully discloses that results are chronological and deduplicated, which the schema cannot convey. However it is silent on pagination behavior despite having limit/offset parameters, and says nothing about permissions or result size.

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 short lines with zero filler, and the most decision-relevant information (what it returns, when to prefer it) is front-loaded ahead of the parameter format note.

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?

An output schema exists, so return values need not be explained. The remaining gap is pagination semantics for limit/offset in a list tool that will plausibly truncate results, which the description never addresses.

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 0%, so the description must compensate. It does add real value for start/end by giving accepted formats (epoch or YYYY-MM-DD), which the bare string schema lacks. But limit and offset are entirely undocumented in both places, leaving half the parameters ambiguous.

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 ('session list') plus distinguishing characteristics (chronological, deduped, time-windowed) in a single clause. It explicitly names search_sessions_tool as the sibling it differs from, so an agent can route without opening either 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?

Explicitly says to prefer this over search_sessions_tool 'for day/week timelines,' naming both the alternative and the condition that selects this tool. Nothing about tool selection is left to inference.

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