Social Democrats co-leader Róisín Shortall has claimed coronavirus vaccines have been 'over-promised' to people here.
She was speaking amid an ongoing row between the European Union and AstraZeneca.
A reduction in supply means Ireland is expected to get around 300,000 doses - instead of an expected 600,000 - by the end of March.
GPs and pharmacists are set to use the AstraZeneca vaccine in surgeries, mass vaccination centres and other venues to inoculate the population - as it can be stored much more easily than the others available.
Ms Shortall is also a member of the Oireachtas Health Committee.
On Friday, both the Health Service Executive (HSE) and the High-Level Taskforce on COVID-19 Vaccination will appear before the committee.
She told The Hard Shoulder she wants clarity around several areas.
"Many of us have been looking for up to date details on what's happening in relation to the vaccine programme.
"There have been a number of setbacks - and much of that the country had no control over, the Government had no control over.
"But I think the key thing is that everybody is kept really well informed about the level of the supplies that we're getting in - I've looked for a daily report on that - the number of supplies that are delivered here, and then the number of vaccines that are actually administered to people".
She said that since Christmas, there has been "a good bit of over-promising" in relation to vaccines.
"I mean it is fantastic news that there is this breakthrough with vaccines being discovered, but they're not by any means a silver bullet.
"And there are ongoing concerns in relation to supplies of the various vaccines, and also about their efficacy.
"How effective are they in different circumstances? And particularly then in relation to the new variants that are emerging.
"We still have to follow all of the advice, we still need to have a clear strategy in relation to how we respond to COVID - and this is going to be required for some time to come.
"And even best case scenario, I think we're talking about most people being vaccinated by the autumn".
Dedicated lead on vaccine rollout
While she said another area of concern is the governance around the entire process.
"Ultimately we know that the Minister for Health is politically responsible for the rollout of the programme.
"But below him then, who is responsible? I think we need a dedicated lead on the rollout of the vaccine programme."
Deputy Shortall acknowledged that while some questions can only be answered by agencies - such as the European Medicines Agency - others can be dealt with here.
"There are then questions that need to be asked here in relation to what is the progress being made, at what stage different cohorts of people are likely to receive their vaccines".
"We need kind of accurate estimates, and if there's an improvement on that - hopefully there will be - well and good."
"But at this stage, you'd have to say an impression was given that lots of people are going to get this very quickly: we have to be realistic about the timescale involved".
And she said questions on other practical issues, such as a registration system, still have to be answered.
"People are wondering do they wait for a call from their GP, or do they have to register themselves.
"And what about those people who don't have IT access, and how are they going to be reached.
"So there's a lot of practical issues like that that we need answers on".
Home quarantine 'crazy stuff'
On travel, Deputy Shortall said the approach being taken is still not enough.
"It's one of the big weak links in relation to the Government's response to COVID.
"For most of the time, there was actually no system in place at all to oversee or control incoming travellers here."
She said less than 20% of people who travel here actually get a follow-up phone call - and only half of those answer the call.
She said asking people to quarantine at home is a contradiction in terms.
"If you are to quarantine because of possible risk, that means you shouldn't be with other people.
"And we're saying to people 'you travel home to go home on the number 16 bus from the airport'.
"How do you travel home? How are you going to be fixed when you get home?... there are no controls in that, no safeguards at all.
"The whole idea of people quarantining in their own home that requires, for a start, that they have a separate bedroom with en-suite facilities, that they've somebody who will deliver their meals to their door.
"It's crazy stuff".