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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered by structured data. The description adds the workflow behavior of calling first at run start, but discloses nothing extra about pagination limits, token expiry semantics, or error conditions beyond what the schema and annotations carry.

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?

Two sentences, front-loaded with the identity/content payload and closed with the action directive; no filler. The contents enumeration is long but each item is a distinct piece of returned information, so it largely earns its space.

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 enumerating return fields is arguably redundant, yet the description still gives the agent enough to decide to call it first in a run. Combined with annotations covering safety, nothing essential for correct invocation is missing; only deeper sibling disambiguation would improve it.

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 optional 'after' cursor, and the schema itself explains the 200-per-page, name-ordered paging model. The description contributes no additional parameter semantics, so the baseline 3 applies.

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 names a concrete resource — the calling KEY's own identity snapshot — and enumerates its contents (peer id, token expiry, mailbox position, memberships with lag, newest-dossier space), which is far more than a restatement of the title. It does not, however, differentiate itself from overlapping siblings like schellingaf_spaces, schellingaf_mailbox or schellingaf_seek, whose data this tool apparently aggregates.

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 gives an explicit trigger ('Call it at the start of a RUN') and a rationale for doing so ('before spending tokens on reading'), which implies a cheaper orientation call preceding read-heavy siblings. There is no explicit when-not guidance or named alternative, so it stops 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.