memory_sessions

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

With no annotations, the description carries the burden and does well: it discloses that archived/excluded ambient sessions are hidden, that includeExcluded requires exact project+sessionId and still hides archived, that invalid filters error, and that agentId defaults to the configured read scope. It stops short of stating explicit permission/auth requirements or any rate limits.

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?

Front-loaded with purpose, then return shape, pagination, parameter behavior, filtering, and sibling routing in a logical order. It is one dense paragraph packing multiple facts per sentence, which costs a little scannability but every sentence earns its place.

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?

No output schema exists, so the description supplies the return shape ({sessions,total,limit,offset,nextOffset} and the empty-result case) itself. For a six-parameter filtered read tool with no annotations, nothing an agent needs to invoke it correctly appears to be missing.

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 only 67%, yet the description adds meaning for all six parameters: agentId's default read scope and '*' cross-agent behavior, project:'*' as a deliberate cross-project read, sessionId selecting one session, includeExcluded's exact-match requirement, and limit's default of 20 / max 500 with nextOffset-driven paging. This fully compensates for the coverage gap.

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 ('Read stored session metadata') plus scope ('in an explicit project') and ordering ('newest startedAt first'). The final sentence distinguishes it from memory_timeline, so an agent can route between the two without opening a 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?

Gives a clear when-to-use signal and names one explicit alternative ('Use memory_timeline for observations within a session'), plus the prerequisite for includeExcluded. It does not distinguish against the wider set of session/recall siblings, which keeps it short of a 5.

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