telegram_sessions

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

Beyond the readOnly/idempotent annotations, it discloses data-minimisation behaviour an agent cannot infer: the address is truncated to its network and the authorisation hash is never returned. It also states the sort order and that no session-termination capability exists anywhere in this server, which prevents a whole class of failed follow-up calls.

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 the returned fields, then usage, then caveats — a sound order. Slightly repetitive: the inability to end a session is stated twice ('Do not use this to end a session; this server has no such tool' and 'nothing in this project ends a session'), which costs a little tightness.

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?

With no output schema, the description carries the return-shape burden itself and does so by listing every returned field, the ordering, and the two redacted values. Nothing an agent needs to call or interpret this tool is 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 description coverage is 100% and the single optional 'account' parameter is already documented there ('Omit when exactly one account is configured'). The description adds nothing about the parameter, 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 the exact resource (authorisations/sessions) and enumerates the returned fields — device, application, coarse location, first sign-in, last activity — plus the ordering ('current one first'). It also explicitly contrasts itself with the sibling telegram_fleet, so an agent can select it 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 an explicit trigger ('when the user asks which devices or apps are signed in, or whether one of them is unfamiliar') and an explicit exclusion ('Do not use this to end a session'), naming the reason and the neighbouring tool that is not a substitute. When-to-use, when-not, and alternative are all covered.

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