filter_sessions

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

With no annotations, the description carries the full burden of behavioral disclosure. It discloses result capping ('Results are capped at 100'), date inclusivity/exclusivity, default scope behavior, and the special provider='codex' mapping. It does not discuss ordering or output format, but an output schema exists and the tool is a read-style listing.

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 compact and front-loaded with the essential purpose. Every sentence adds distinct value: purpose, when to use, when not to use, special provider handling, date semantics, and scope behavior.

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 15-parameter filtering tool with no annotations and no schema descriptions, the description is unusually complete. It covers selection criteria, exclusion criteria, date/scope/provider nuances, and result limits; the existing output schema covers return shape.

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 0%, so the description must compensate. It explains the non-ovious semantics of scope, date_from/date_to, provider, and the minimum-count/code-change filters. It does not individually explain limit, file_path, model_family, or include_changed_files, but these are fairly inferable and the schema provides titles.

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 opens with a specific verb and resource: 'List sessions by metadata using authoritative Postgres filters, without semantic search.' It also explicitly distinguishes itself from the sibling search_sessions, so an agent can tell them apart without inspecting schemas.

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?

It provides explicit when-to-use guidance ('Use when the user provides no semantic text query...'), what not to do ('Do not invent search text'), and names the alternative tool for semantic-topic queries ('use search_sissions'). It also covers date semantics and scope behavior.

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