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

With readOnlyHint/destructiveHint/openWorldHint already declaring the safety profile, the description adds three useful facts: results are finite rather than a live stream, limit is capped at 1000, and secrets are redacted in output. It omits pagination/cursor behavior and whether an unfiltered call across an environment could be expensive, which matters for a 12-param read tool.

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 sentences, front-loaded with the scoping rule and with no filler. The telegraphic style ('limit max 1000. Secrets redacted.') is efficient but clipped enough that it reads as notes rather than a coherent instruction.

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 described, and the annotations cover safety, which keeps the burden low. The remaining gap is that a 12-parameter tool with zero required parameters gives no hint about sensible defaults or minimum viable calls, so an agent must construct calls largely from the schema alone.

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 only 17%, so the description must carry weight, and it does explain the single most important semantic the schema cannot express: deployment_id yields build/runtime logs while project+environment yields environment logs. However, it says nothing about text, level, service, since/until, or the filter syntax, leaving most of the 12 parameters unexplained in both places.

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 specific resource (historical logs) and its scoping modes, and 'finite' plus the deployment_id vs project+environment split make the tool's domain clear. It stops short of naming the siblings it overlaps with (railway_errors_recent, railway_incident_diagnosis), so an agent still has to infer the boundary.

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 concrete routing advice between parameter sets: use deployment_id for build/runtime logs, or project+environment for environment logs. That is real usage guidance for invocation, but there is nothing about when to prefer this tool over railway_errors_recent or railway_incident_diagnosis, and no exclusions.

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